diff options
Diffstat (limited to 'drivers/tty/serial/msm_serial_hs.c')
| -rw-r--r-- | drivers/tty/serial/msm_serial_hs.c | 1880 |
1 files changed, 1880 insertions, 0 deletions
diff --git a/drivers/tty/serial/msm_serial_hs.c b/drivers/tty/serial/msm_serial_hs.c new file mode 100644 index 000000000000..2e7fc9cee9cc --- /dev/null +++ b/drivers/tty/serial/msm_serial_hs.c @@ -0,0 +1,1880 @@ +/* + * MSM 7k/8k High speed uart driver + * + * Copyright (c) 2007-2011, Code Aurora Forum. All rights reserved. + * Copyright (c) 2008 Google Inc. + * Modified: Nick Pelly <npelly@google.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * version 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. + * See the GNU General Public License for more details. + * + * Has optional support for uart power management independent of linux + * suspend/resume: + * + * RX wakeup. + * UART wakeup can be triggered by RX activity (using a wakeup GPIO on the + * UART RX pin). This should only be used if there is not a wakeup + * GPIO on the UART CTS, and the first RX byte is known (for example, with the + * Bluetooth Texas Instruments HCILL protocol), since the first RX byte will + * always be lost. RTS will be asserted even while the UART is off in this mode + * of operation. See msm_serial_hs_platform_data.rx_wakeup_irq. + */ + +#include <linux/module.h> + +#include <linux/serial.h> +#include <linux/serial_core.h> +#include <linux/slab.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/io.h> +#include <linux/ioport.h> +#include <linux/kernel.h> +#include <linux/timer.h> +#include <linux/clk.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/dma-mapping.h> +#include <linux/dmapool.h> +#include <linux/wait.h> +#include <linux/workqueue.h> + +#include <linux/atomic.h> +#include <asm/irq.h> +#include <asm/system.h> + +#include <mach/hardware.h> +#include <mach/dma.h> +#include <linux/platform_data/msm_serial_hs.h> + +/* HSUART Registers */ +#define UARTDM_MR1_ADDR 0x0 +#define UARTDM_MR2_ADDR 0x4 + +/* Data Mover result codes */ +#define RSLT_FIFO_CNTR_BMSK (0xE << 28) +#define RSLT_VLD BIT(1) + +/* write only register */ +#define UARTDM_CSR_ADDR 0x8 +#define UARTDM_CSR_115200 0xFF +#define UARTDM_CSR_57600 0xEE +#define UARTDM_CSR_38400 0xDD +#define UARTDM_CSR_28800 0xCC +#define UARTDM_CSR_19200 0xBB +#define UARTDM_CSR_14400 0xAA +#define UARTDM_CSR_9600 0x99 +#define UARTDM_CSR_7200 0x88 +#define UARTDM_CSR_4800 0x77 +#define UARTDM_CSR_3600 0x66 +#define UARTDM_CSR_2400 0x55 +#define UARTDM_CSR_1200 0x44 +#define UARTDM_CSR_600 0x33 +#define UARTDM_CSR_300 0x22 +#define UARTDM_CSR_150 0x11 +#define UARTDM_CSR_75 0x00 + +/* write only register */ +#define UARTDM_TF_ADDR 0x70 +#define UARTDM_TF2_ADDR 0x74 +#define UARTDM_TF3_ADDR 0x78 +#define UARTDM_TF4_ADDR 0x7C + +/* write only register */ +#define UARTDM_CR_ADDR 0x10 +#define UARTDM_IMR_ADDR 0x14 + +#define UARTDM_IPR_ADDR 0x18 +#define UARTDM_TFWR_ADDR 0x1c +#define UARTDM_RFWR_ADDR 0x20 +#define UARTDM_HCR_ADDR 0x24 +#define UARTDM_DMRX_ADDR 0x34 +#define UARTDM_IRDA_ADDR 0x38 +#define UARTDM_DMEN_ADDR 0x3c + +/* UART_DM_NO_CHARS_FOR_TX */ +#define UARTDM_NCF_TX_ADDR 0x40 + +#define UARTDM_BADR_ADDR 0x44 + +#define UARTDM_SIM_CFG_ADDR 0x80 +/* Read Only register */ +#define UARTDM_SR_ADDR 0x8 + +/* Read Only register */ +#define UARTDM_RF_ADDR 0x70 +#define UARTDM_RF2_ADDR 0x74 +#define UARTDM_RF3_ADDR 0x78 +#define UARTDM_RF4_ADDR 0x7C + +/* Read Only register */ +#define UARTDM_MISR_ADDR 0x10 + +/* Read Only register */ +#define UARTDM_ISR_ADDR 0x14 +#define UARTDM_RX_TOTAL_SNAP_ADDR 0x38 + +#define UARTDM_RXFS_ADDR 0x50 + +/* Register field Mask Mapping */ +#define UARTDM_SR_PAR_FRAME_BMSK BIT(5) +#define UARTDM_SR_OVERRUN_BMSK BIT(4) +#define UARTDM_SR_TXEMT_BMSK BIT(3) +#define UARTDM_SR_TXRDY_BMSK BIT(2) +#define UARTDM_SR_RXRDY_BMSK BIT(0) + +#define UARTDM_CR_TX_DISABLE_BMSK BIT(3) +#define UARTDM_CR_RX_DISABLE_BMSK BIT(1) +#define UARTDM_CR_TX_EN_BMSK BIT(2) +#define UARTDM_CR_RX_EN_BMSK BIT(0) + +/* UARTDM_CR channel_comman bit value (register field is bits 8:4) */ +#define RESET_RX 0x10 +#define RESET_TX 0x20 +#define RESET_ERROR_STATUS 0x30 +#define RESET_BREAK_INT 0x40 +#define START_BREAK 0x50 +#define STOP_BREAK 0x60 +#define RESET_CTS 0x70 +#define RESET_STALE_INT 0x80 +#define RFR_LOW 0xD0 +#define RFR_HIGH 0xE0 +#define CR_PROTECTION_EN 0x100 +#define STALE_EVENT_ENABLE 0x500 +#define STALE_EVENT_DISABLE 0x600 +#define FORCE_STALE_EVENT 0x400 +#define CLEAR_TX_READY 0x300 +#define RESET_TX_ERROR 0x800 +#define RESET_TX_DONE 0x810 + +#define UARTDM_MR1_AUTO_RFR_LEVEL1_BMSK 0xffffff00 +#define UARTDM_MR1_AUTO_RFR_LEVEL0_BMSK 0x3f +#define UARTDM_MR1_CTS_CTL_BMSK 0x40 +#define UARTDM_MR1_RX_RDY_CTL_BMSK 0x80 + +#define UARTDM_MR2_ERROR_MODE_BMSK 0x40 +#define UARTDM_MR2_BITS_PER_CHAR_BMSK 0x30 + +/* bits per character configuration */ +#define FIVE_BPC (0 << 4) +#define SIX_BPC (1 << 4) +#define SEVEN_BPC (2 << 4) +#define EIGHT_BPC (3 << 4) + +#define UARTDM_MR2_STOP_BIT_LEN_BMSK 0xc +#define STOP_BIT_ONE (1 << 2) +#define STOP_BIT_TWO (3 << 2) + +#define UARTDM_MR2_PARITY_MODE_BMSK 0x3 + +/* Parity configuration */ +#define NO_PARITY 0x0 +#define EVEN_PARITY 0x1 +#define ODD_PARITY 0x2 +#define SPACE_PARITY 0x3 + +#define UARTDM_IPR_STALE_TIMEOUT_MSB_BMSK 0xffffff80 +#define UARTDM_IPR_STALE_LSB_BMSK 0x1f + +/* These can be used for both ISR and IMR register */ +#define UARTDM_ISR_TX_READY_BMSK BIT(7) +#define UARTDM_ISR_CURRENT_CTS_BMSK BIT(6) +#define UARTDM_ISR_DELTA_CTS_BMSK BIT(5) +#define UARTDM_ISR_RXLEV_BMSK BIT(4) +#define UARTDM_ISR_RXSTALE_BMSK BIT(3) +#define UARTDM_ISR_RXBREAK_BMSK BIT(2) +#define UARTDM_ISR_RXHUNT_BMSK BIT(1) +#define UARTDM_ISR_TXLEV_BMSK BIT(0) + +/* Field definitions for UART_DM_DMEN*/ +#define UARTDM_TX_DM_EN_BMSK 0x1 +#define UARTDM_RX_DM_EN_BMSK 0x2 + +#define UART_FIFOSIZE 64 +#define UARTCLK 7372800 + +/* Rx DMA request states */ +enum flush_reason { + FLUSH_NONE, + FLUSH_DATA_READY, + FLUSH_DATA_INVALID, /* values after this indicate invalid data */ + FLUSH_IGNORE = FLUSH_DATA_INVALID, + FLUSH_STOP, + FLUSH_SHUTDOWN, +}; + +/* UART clock states */ +enum msm_hs_clk_states_e { + MSM_HS_CLK_PORT_OFF, /* port not in use */ + MSM_HS_CLK_OFF, /* clock disabled */ + MSM_HS_CLK_REQUEST_OFF, /* disable after TX and RX flushed */ + MSM_HS_CLK_ON, /* clock enabled */ +}; + +/* Track the forced RXSTALE flush during clock off sequence. + * These states are only valid during MSM_HS_CLK_REQUEST_OFF */ +enum msm_hs_clk_req_off_state_e { + CLK_REQ_OFF_START, + CLK_REQ_OFF_RXSTALE_ISSUED, + CLK_REQ_OFF_FLUSH_ISSUED, + CLK_REQ_OFF_RXSTALE_FLUSHED, +}; + +/** + * struct msm_hs_tx + * @tx_ready_int_en: ok to dma more tx? + * @dma_in_flight: tx dma in progress + * @xfer: top level DMA command pointer structure + * @command_ptr: third level command struct pointer + * @command_ptr_ptr: second level command list struct pointer + * @mapped_cmd_ptr: DMA view of third level command struct + * @mapped_cmd_ptr_ptr: DMA view of second level command list struct + * @tx_count: number of bytes to transfer in DMA transfer + * @dma_base: DMA view of UART xmit buffer + * + * This structure describes a single Tx DMA transaction. MSM DMA + * commands have two levels of indirection. The top level command + * ptr points to a list of command ptr which in turn points to a + * single DMA 'command'. In our case each Tx transaction consists + * of a single second level pointer pointing to a 'box type' command. + */ +struct msm_hs_tx { + unsigned int tx_ready_int_en; + unsigned int dma_in_flight; + struct msm_dmov_cmd xfer; + dmov_box *command_ptr; + u32 *command_ptr_ptr; + dma_addr_t mapped_cmd_ptr; + dma_addr_t mapped_cmd_ptr_ptr; + int tx_count; + dma_addr_t dma_base; +}; + +/** + * struct msm_hs_rx + * @flush: Rx DMA request state + * @xfer: top level DMA command pointer structure + * @cmdptr_dmaaddr: DMA view of second level command structure + * @command_ptr: third level DMA command pointer structure + * @command_ptr_ptr: second level DMA command list pointer + * @mapped_cmd_ptr: DMA view of the third level command structure + * @wait: wait for DMA completion before shutdown + * @buffer: destination buffer for RX DMA + * @rbuffer: DMA view of buffer + * @pool: dma pool out of which coherent rx buffer is allocated + * @tty_work: private work-queue for tty flip buffer push task + * + * This structure describes a single Rx DMA transaction. Rx DMA + * transactions use box mode DMA commands. + */ +struct msm_hs_rx { + enum flush_reason flush; + struct msm_dmov_cmd xfer; + dma_addr_t cmdptr_dmaaddr; + dmov_box *command_ptr; + u32 *command_ptr_ptr; + dma_addr_t mapped_cmd_ptr; + wait_queue_head_t wait; + dma_addr_t rbuffer; + unsigned char *buffer; + struct dma_pool *pool; + struct work_struct tty_work; +}; + +/** + * struct msm_hs_rx_wakeup + * @irq: IRQ line to be configured as interrupt source on Rx activity + * @ignore: boolean value. 1 = ignore the wakeup interrupt + * @rx_to_inject: extra character to be inserted to Rx tty on wakeup + * @inject_rx: 1 = insert rx_to_inject. 0 = do not insert extra character + * + * This is an optional structure required for UART Rx GPIO IRQ based + * wakeup from low power state. UART wakeup can be triggered by RX activity + * (using a wakeup GPIO on the UART RX pin). This should only be used if + * there is not a wakeup GPIO on the UART CTS, and the first RX byte is + * known (eg., with the Bluetooth Texas Instruments HCILL protocol), + * since the first RX byte will always be lost. RTS will be asserted even + * while the UART is clocked off in this mode of operation. + */ +struct msm_hs_rx_wakeup { + int irq; /* < 0 indicates low power wakeup disabled */ + unsigned char ignore; + unsigned char inject_rx; + char rx_to_inject; +}; + +/** + * struct msm_hs_port + * @uport: embedded uart port structure + * @imr_reg: shadow value of UARTDM_IMR + * @clk: uart input clock handle + * @tx: Tx transaction related data structure + * @rx: Rx transaction related data structure + * @dma_tx_channel: Tx DMA command channel + * @dma_rx_channel Rx DMA command channel + * @dma_tx_crci: Tx channel rate control interface number + * @dma_rx_crci: Rx channel rate control interface number + * @clk_off_timer: Timer to poll DMA event completion before clock off + * @clk_off_delay: clk_off_timer poll interval + * @clk_state: overall clock state + * @clk_req_off_state: post flush clock states + * @rx_wakeup: optional rx_wakeup feature related data + * @exit_lpm_cb: optional callback to exit low power mode + * + * Low level serial port structure. + */ +struct msm_hs_port { + struct uart_port uport; + unsigned long imr_reg; + struct clk *clk; + struct msm_hs_tx tx; + struct msm_hs_rx rx; + + int dma_tx_channel; + int dma_rx_channel; + int dma_tx_crci; + int dma_rx_crci; + + struct hrtimer clk_off_timer; + ktime_t clk_off_delay; + enum msm_hs_clk_states_e clk_state; + enum msm_hs_clk_req_off_state_e clk_req_off_state; + + struct msm_hs_rx_wakeup rx_wakeup; + void (*exit_lpm_cb)(struct uart_port *); +}; + +#define MSM_UARTDM_BURST_SIZE 16 /* DM burst size (in bytes) */ +#define UARTDM_TX_BUF_SIZE UART_XMIT_SIZE +#define UARTDM_RX_BUF_SIZE 512 + +#define UARTDM_NR 2 + +static struct msm_hs_port q_uart_port[UARTDM_NR]; +static struct platform_driver msm_serial_hs_platform_driver; +static struct uart_driver msm_hs_driver; +static struct uart_ops msm_hs_ops; +static struct workqueue_struct *msm_hs_workqueue; + +#define UARTDM_TO_MSM(uart_port) \ + container_of((uart_port), struct msm_hs_port, uport) + +static unsigned int use_low_power_rx_wakeup(struct msm_hs_port + *msm_uport) +{ + return (msm_uport->rx_wakeup.irq >= 0); +} + +static unsigned int msm_hs_read(struct uart_port *uport, + unsigned int offset) +{ + return ioread32(uport->membase + offset); +} + +static void msm_hs_write(struct uart_port *uport, unsigned int offset, + unsigned int value) +{ + iowrite32(value, uport->membase + offset); +} + +static void msm_hs_release_port(struct uart_port *port) +{ + iounmap(port->membase); +} + +static int msm_hs_request_port(struct uart_port *port) +{ + port->membase = ioremap(port->mapbase, PAGE_SIZE); + if (unlikely(!port->membase)) + return -ENOMEM; + + /* configure the CR Protection to Enable */ + msm_hs_write(port, UARTDM_CR_ADDR, CR_PROTECTION_EN); + return 0; +} + +static int __devexit msm_hs_remove(struct platform_device *pdev) +{ + + struct msm_hs_port *msm_uport; + struct device *dev; + + if (pdev->id < 0 || pdev->id >= UARTDM_NR) { + printk(KERN_ERR "Invalid plaform device ID = %d\n", pdev->id); + return -EINVAL; + } + + msm_uport = &q_uart_port[pdev->id]; + dev = msm_uport->uport.dev; + + dma_unmap_single(dev, msm_uport->rx.mapped_cmd_ptr, sizeof(dmov_box), + DMA_TO_DEVICE); + dma_pool_free(msm_uport->rx.pool, msm_uport->rx.buffer, + msm_uport->rx.rbuffer); + dma_pool_destroy(msm_uport->rx.pool); + + dma_unmap_single(dev, msm_uport->rx.cmdptr_dmaaddr, sizeof(u32 *), + DMA_TO_DEVICE); + dma_unmap_single(dev, msm_uport->tx.mapped_cmd_ptr_ptr, sizeof(u32 *), + DMA_TO_DEVICE); + dma_unmap_single(dev, msm_uport->tx.mapped_cmd_ptr, sizeof(dmov_box), + DMA_TO_DEVICE); + + uart_remove_one_port(&msm_hs_driver, &msm_uport->uport); + clk_put(msm_uport->clk); + + /* Free the tx resources */ + kfree(msm_uport->tx.command_ptr); + kfree(msm_uport->tx.command_ptr_ptr); + + /* Free the rx resources */ + kfree(msm_uport->rx.command_ptr); + kfree(msm_uport->rx.command_ptr_ptr); + + iounmap(msm_uport->uport.membase); + + return 0; +} + +static int msm_hs_init_clk_locked(struct uart_port *uport) +{ + int ret; + struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport); + + ret = clk_enable(msm_uport->clk); + if (ret) { + printk(KERN_ERR "Error could not turn on UART clk\n"); + return ret; + } + + /* Set up the MREG/NREG/DREG/MNDREG */ + ret = clk_set_rate(msm_uport->clk, uport->uartclk); + if (ret) { + printk(KERN_WARNING "Error setting clock rate on UART\n"); + clk_disable(msm_uport->clk); + return ret; + } + + msm_uport->clk_state = MSM_HS_CLK_ON; + return 0; +} + +/* Enable and Disable clocks (Used for power management) */ +static void msm_hs_pm(struct uart_port *uport, unsigned int state, + unsigned int oldstate) +{ + struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport); + + if (use_low_power_rx_wakeup(msm_uport) || + msm_uport->exit_lpm_cb) + return; /* ignore linux PM states, + use msm_hs_request_clock API */ + + switch (state) { + case 0: + clk_enable(msm_uport->clk); + break; + case 3: + clk_disable(msm_uport->clk); + break; + default: + dev_err(uport->dev, "msm_serial: Unknown PM state %d\n", + state); + } +} + +/* + * programs the UARTDM_CSR register with correct bit rates + * + * Interrupts should be disabled before we are called, as + * we modify Set Baud rate + * Set receive stale interrupt level, dependant on Bit Rate + * Goal is to have around 8 ms before indicate stale. + * roundup (((Bit Rate * .008) / 10) + 1 + */ +static void msm_hs_set_bps_locked(struct uart_port *uport, + unsigned int bps) +{ + unsigned long rxstale; + unsigned long data; + struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport); + + switch (bps) { + case 300: + msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_75); + rxstale = 1; + break; + case 600: + msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_150); + rxstale = 1; + break; + case 1200: + msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_300); + rxstale = 1; + break; + case 2400: + msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_600); + rxstale = 1; + break; + case 4800: + msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_1200); + rxstale = 1; + break; + case 9600: + msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_2400); + rxstale = 2; + break; + case 14400: + msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_3600); + rxstale = 3; + break; + case 19200: + msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_4800); + rxstale = 4; + break; + case 28800: + msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_7200); + rxstale = 6; + break; + case 38400: + msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_9600); + rxstale = 8; + break; + case 57600: + msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_14400); + rxstale = 16; + break; + case 76800: + msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_19200); + rxstale = 16; + break; + case 115200: + msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_28800); + rxstale = 31; + break; + case 230400: + msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_57600); + rxstale = 31; + break; + case 460800: + msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_115200); + rxstale = 31; + break; + case 4000000: + case 3686400: + case 3200000: + case 3500000: + case 3000000: + case 2500000: + case 1500000: + case 1152000: + case 1000000: + case 921600: + msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_115200); + rxstale = 31; + break; + default: + msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_2400); + /* default to 9600 */ + bps = 9600; + rxstale = 2; + break; + } + if (bps > 460800) + uport->uartclk = bps * 16; + else + uport->uartclk = UARTCLK; + + if (clk_set_rate(msm_uport->clk, uport->uartclk)) { + printk(KERN_WARNING "Error setting clock rate on UART\n"); + return; + } + + data = rxstale & UARTDM_IPR_STALE_LSB_BMSK; + data |= UARTDM_IPR_STALE_TIMEOUT_MSB_BMSK & (rxstale << 2); + + msm_hs_write(uport, UARTDM_IPR_ADDR, data); +} + +/* + * termios : new ktermios + * oldtermios: old ktermios previous setting + * + * Configure the serial port + */ +static void msm_hs_set_termios(struct uart_port *uport, + struct ktermios *termios, + struct ktermios *oldtermios) +{ + unsigned int bps; + unsigned long data; + unsigned long flags; + unsigned int c_cflag = termios->c_cflag; + struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport); + + spin_lock_irqsave(&uport->lock, flags); + clk_enable(msm_uport->clk); + + /* 300 is the minimum baud support by the driver */ + bps = uart_get_baud_rate(uport, termios, oldtermios, 200, 4000000); + + /* Temporary remapping 200 BAUD to 3.2 mbps */ + if (bps == 200) + bps = 3200000; + + msm_hs_set_bps_locked(uport, bps); + + data = msm_hs_read(uport, UARTDM_MR2_ADDR); + data &= ~UARTDM_MR2_PARITY_MODE_BMSK; + /* set parity */ + if (PARENB == (c_cflag & PARENB)) { + if (PARODD == (c_cflag & PARODD)) + data |= ODD_PARITY; + else if (CMSPAR == (c_cflag & CMSPAR)) + data |= SPACE_PARITY; + else + data |= EVEN_PARITY; + } + + /* Set bits per char */ + data &= ~UARTDM_MR2_BITS_PER_CHAR_BMSK; + + switch (c_cflag & CSIZE) { + case CS5: + data |= FIVE_BPC; + break; + case CS6: + data |= SIX_BPC; + break; + case CS7: + data |= SEVEN_BPC; + break; + default: + data |= EIGHT_BPC; + break; + } + /* stop bits */ + if (c_cflag & CSTOPB) { + data |= STOP_BIT_TWO; + } else { + /* otherwise 1 stop bit */ + data |= STOP_BIT_ONE; + } + data |= UARTDM_MR2_ERROR_MODE_BMSK; + /* write parity/bits per char/stop bit configuration */ + msm_hs_write(uport, UARTDM_MR2_ADDR, data); + + /* Configure HW flow control */ + data = msm_hs_read(uport, UARTDM_MR1_ADDR); + + data &= ~(UARTDM_MR1_CTS_CTL_BMSK | UARTDM_MR1_RX_RDY_CTL_BMSK); + + if (c_cflag & CRTSCTS) { + data |= UARTDM_MR1_CTS_CTL_BMSK; + data |= UARTDM_MR1_RX_RDY_CTL_BMSK; + } + + msm_hs_write(uport, UARTDM_MR1_ADDR, data); + + uport->ignore_status_mask = termios->c_iflag & INPCK; + uport->ignore_status_mask |= termios->c_iflag & IGNPAR; + uport->read_status_mask = (termios->c_cflag & CREAD); + + msm_hs_write(uport, UARTDM_IMR_ADDR, 0); + + /* Set Transmit software time out */ + uart_update_timeout(uport, c_cflag, bps); + + msm_hs_write(uport, UARTDM_CR_ADDR, RESET_RX); + msm_hs_write(uport, UARTDM_CR_ADDR, RESET_TX); + + if (msm_uport->rx.flush == FLUSH_NONE) { + msm_uport->rx.flush = FLUSH_IGNORE; + msm_dmov_stop_cmd(msm_uport->dma_rx_channel, NULL, 1); + } + + msm_hs_write(uport, UARTDM_IMR_ADDR, msm_uport->imr_reg); + + clk_disable(msm_uport->clk); + spin_unlock_irqrestore(&uport->lock, flags); +} + +/* + * Standard API, Transmitter + * Any character in the transmit shift register is sent + */ +static unsigned int msm_hs_tx_empty(struct uart_port *uport) +{ + unsigned int data; + unsigned int ret = 0; + struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport); + + clk_enable(msm_uport->clk); + + data = msm_hs_read(uport, UARTDM_SR_ADDR); + if (data & UARTDM_SR_TXEMT_BMSK) + ret = TIOCSER_TEMT; + + clk_disable(msm_uport->clk); + + return ret; +} + +/* + * Standard API, Stop transmitter. + * Any character in the transmit shift register is sent as + * well as the current data mover transfer . + */ +static void msm_hs_stop_tx_locked(struct uart_port *uport) +{ + struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport); + + msm_uport->tx.tx_ready_int_en = 0; +} + +/* + * Standard API, Stop receiver as soon as possible. + * + * Function immediately terminates the operation of the + * channel receiver and any incoming characters are lost. None + * of the receiver status bits are affected by this command and + * characters that are already in the receive FIFO there. + */ +static void msm_hs_stop_rx_locked(struct uart_port *uport) +{ + struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport); + unsigned int data; + + clk_enable(msm_uport->clk); + + /* disable dlink */ + data = msm_hs_read(uport, UARTDM_DMEN_ADDR); + data &= ~UARTDM_RX_DM_EN_BMSK; + msm_hs_write(uport, UARTDM_DMEN_ADDR, data); + + /* Disable the receiver */ + if (msm_uport->rx.flush == FLUSH_NONE) + msm_dmov_stop_cmd(msm_uport->dma_rx_channel, NULL, 1); + + if (msm_uport->rx.flush != FLUSH_SHUTDOWN) + msm_uport->rx.flush = FLUSH_STOP; + + clk_disable(msm_uport->clk); +} + +/* Transmit the next chunk of data */ +static void msm_hs_submit_tx_locked(struct uart_port *uport) +{ + int left; + int tx_count; + dma_addr_t src_addr; + struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport); + struct msm_hs_tx *tx = &msm_uport->tx; + struct circ_buf *tx_buf = &msm_uport->uport.state->xmit; + + if (uart_circ_empty(tx_buf) || uport->state->port.tty->stopped) { + msm_hs_stop_tx_locked(uport); + return; + } + + tx->dma_in_flight = 1; + + tx_count = uart_circ_chars_pending(tx_buf); + + if (UARTDM_TX_BUF_SIZE < tx_count) + tx_count = UARTDM_TX_BUF_SIZE; + + left = UART_XMIT_SIZE - tx_buf->tail; + + if (tx_count > left) + tx_count = left; + + src_addr = tx->dma_base + tx_buf->tail; + dma_sync_single_for_device(uport->dev, src_addr, tx_count, + DMA_TO_DEVICE); + + tx->command_ptr->num_rows = (((tx_count + 15) >> 4) << 16) | + ((tx_count + 15) >> 4); + tx->command_ptr->src_row_addr = src_addr; + + dma_sync_single_for_device(uport->dev, tx->mapped_cmd_ptr, + sizeof(dmov_box), DMA_TO_DEVICE); + + *tx->command_ptr_ptr = CMD_PTR_LP | DMOV_CMD_ADDR(tx->mapped_cmd_ptr); + + dma_sync_single_for_device(uport->dev, tx->mapped_cmd_ptr_ptr, + sizeof(u32 *), DMA_TO_DEVICE); + + /* Save tx_count to use in Callback */ + tx->tx_count = tx_count; + msm_hs_write(uport, UARTDM_NCF_TX_ADDR, tx_count); + + /* Disable the tx_ready interrupt */ + msm_uport->imr_reg &= ~UARTDM_ISR_TX_READY_BMSK; + msm_hs_write(uport, UARTDM_IMR_ADDR, msm_uport->imr_reg); + msm_dmov_enqueue_cmd(msm_uport->dma_tx_channel, &tx->xfer); +} + +/* Start to receive the next chunk of data */ +static void msm_hs_start_rx_locked(struct uart_port *uport) +{ + struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport); + + msm_hs_write(uport, UARTDM_CR_ADDR, RESET_STALE_INT); + msm_hs_write(uport, UARTDM_DMRX_ADDR, UARTDM_RX_BUF_SIZE); + msm_hs_write(uport, UARTDM_CR_ADDR, STALE_EVENT_ENABLE); + msm_uport->imr_reg |= UARTDM_ISR_RXLEV_BMSK; + msm_hs_write(uport, UARTDM_IMR_ADDR, msm_uport->imr_reg); + + msm_uport->rx.flush = FLUSH_NONE; + msm_dmov_enqueue_cmd(msm_uport->dma_rx_channel, &msm_uport->rx.xfer); + + /* might have finished RX and be ready to clock off */ + hrtimer_start(&msm_uport->clk_off_timer, msm_uport->clk_off_delay, + HRTIMER_MODE_REL); +} + +/* Enable the transmitter Interrupt */ +static void msm_hs_start_tx_locked(struct uart_port *uport) +{ + struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport); + + clk_enable(msm_uport->clk); + + if (msm_uport->exit_lpm_cb) + msm_uport->exit_lpm_cb(uport); + + if (msm_uport->tx.tx_ready_int_en == 0) { + msm_uport->tx.tx_ready_int_en = 1; + msm_hs_submit_tx_locked(uport); + } + + clk_disable(msm_uport->clk); +} + +/* + * This routine is called when we are done with a DMA transfer + * + * This routine is registered with Data mover when we set + * up a Data Mover transfer. It is called from Data mover ISR + * when the DMA transfer is done. + */ +static void msm_hs_dmov_tx_callback(struct msm_dmov_cmd *cmd_ptr, + unsigned int result, + struct msm_dmov_errdata *err) +{ + unsigned long flags; + struct msm_hs_port *msm_uport; + + /* DMA did not finish properly */ + WARN_ON((((result & RSLT_FIFO_CNTR_BMSK) >> 28) == 1) && + !(result & RSLT_VLD)); + + msm_uport = container_of(cmd_ptr, struct msm_hs_port, tx.xfer); + + spin_lock_irqsave(&msm_uport->uport.lock, flags); + clk_enable(msm_uport->clk); + + msm_uport->imr_reg |= UARTDM_ISR_TX_READY_BMSK; + msm_hs_write(&msm_uport->uport, UARTDM_IMR_ADDR, msm_uport->imr_reg); + + clk_disable(msm_uport->clk); + spin_unlock_irqrestore(&msm_uport->uport.lock, flags); +} + +/* + * This routine is called when we are done with a DMA transfer or the + * a flush has been sent to the data mover driver. + * + * This routine is registered with Data mover when we set up a Data Mover + * transfer. It is called from Data mover ISR when the DMA transfer is done. + */ +static void msm_hs_dmov_rx_callback(struct msm_dmov_cmd *cmd_ptr, + unsigned int result, + struct msm_dmov_errdata *err) +{ + int retval; + int rx_count; + unsigned long status; + unsigned int error_f = 0; + unsigned long flags; + unsigned int flush; + struct tty_struct *tty; + struct uart_port *uport; + struct msm_hs_port *msm_uport; + + msm_uport = container_of(cmd_ptr, struct msm_hs_port, rx.xfer); + uport = &msm_uport->uport; + + spin_lock_irqsave(&uport->lock, flags); + clk_enable(msm_uport->clk); + + tty = uport->state->port.tty; + + msm_hs_write(uport, UARTDM_CR_ADDR, STALE_EVENT_DISABLE); + + status = msm_hs_read(uport, UARTDM_SR_ADDR); + + /* overflow is not connect to data in a FIFO */ + if (unlikely((status & UARTDM_SR_OVERRUN_BMSK) && + (uport->read_status_mask & CREAD))) { + tty_insert_flip_char(tty, 0, TTY_OVERRUN); + uport->icount.buf_overrun++; + error_f = 1; + } + + if (!(uport->ignore_status_mask & INPCK)) + status = status & ~(UARTDM_SR_PAR_FRAME_BMSK); + + if (unlikely(status & UARTDM_SR_PAR_FRAME_BMSK)) { + /* Can not tell difference between parity & frame error */ + uport->icount.parity++; + error_f = 1; + if (uport->ignore_status_mask & IGNPAR) + tty_insert_flip_char(tty, 0, TTY_PARITY); + } + + if (error_f) + msm_hs_write(uport, UARTDM_CR_ADDR, RESET_ERROR_STATUS); + + if (msm_uport->clk_req_off_state == CLK_REQ_OFF_FLUSH_ISSUED) + msm_uport->clk_req_off_state = CLK_REQ_OFF_RXSTALE_FLUSHED; + + flush = msm_uport->rx.flush; + if (flush == FLUSH_IGNORE) + msm_hs_start_rx_locked(uport); + if (flush == FLUSH_STOP) + msm_uport->rx.flush = FLUSH_SHUTDOWN; + if (flush >= FLUSH_DATA_INVALID) + goto out; + + rx_count = msm_hs_read(uport, UARTDM_RX_TOTAL_SNAP_ADDR); + + if (0 != (uport->read_status_mask & CREAD)) { + retval = tty_insert_flip_string(tty, msm_uport->rx.buffer, + rx_count); + BUG_ON(retval != rx_count); + } + + msm_hs_start_rx_locked(uport); + +out: + clk_disable(msm_uport->clk); + + spin_unlock_irqrestore(&uport->lock, flags); + + if (flush < FLUSH_DATA_INVALID) + queue_work(msm_hs_workqueue, &msm_uport->rx.tty_work); +} + +static void msm_hs_tty_flip_buffer_work(struct work_struct *work) +{ + struct msm_hs_port *msm_uport = + container_of(work, struct msm_hs_port, rx.tty_work); + struct tty_struct *tty = msm_uport->uport.state->port.tty; + + tty_flip_buffer_push(tty); +} + +/* + * Standard API, Current states of modem control inputs + * + * Since CTS can be handled entirely by HARDWARE we always + * indicate clear to send and count on the TX FIFO to block when + * it fills up. + * + * - TIOCM_DCD + * - TIOCM_CTS + * - TIOCM_DSR + * - TIOCM_RI + * (Unsupported) DCD and DSR will return them high. RI will return low. + */ +static unsigned int msm_hs_get_mctrl_locked(struct uart_port *uport) +{ + return TIOCM_DSR | TIOCM_CAR | TIOCM_CTS; +} + +/* + * True enables UART auto RFR, which indicates we are ready for data if the RX + * buffer is not full. False disables auto RFR, and deasserts RFR to indicate + * we are not ready for data. Must be called with UART clock on. + */ +static void set_rfr_locked(struct uart_port *uport, int auto_rfr) +{ + unsigned int data; + + data = msm_hs_read(uport, UARTDM_MR1_ADDR); + + if (auto_rfr) { + /* enable auto ready-for-receiving */ + data |= UARTDM_MR1_RX_RDY_CTL_BMSK; + msm_hs_write(uport, UARTDM_MR1_ADDR, data); + } else { + /* disable auto ready-for-receiving */ + data &= ~UARTDM_MR1_RX_RDY_CTL_BMSK; + msm_hs_write(uport, UARTDM_MR1_ADDR, data); + /* RFR is active low, set high */ + msm_hs_write(uport, UARTDM_CR_ADDR, RFR_HIGH); + } +} + +/* + * Standard API, used to set or clear RFR + */ +static void msm_hs_set_mctrl_locked(struct uart_port *uport, + unsigned int mctrl) +{ + unsigned int auto_rfr; + struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport); + + clk_enable(msm_uport->clk); + + auto_rfr = TIOCM_RTS & mctrl ? 1 : 0; + set_rfr_locked(uport, auto_rfr); + + clk_disable(msm_uport->clk); +} + +/* Standard API, Enable modem status (CTS) interrupt */ +static void msm_hs_enable_ms_locked(struct uart_port *uport) +{ + struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport); + + clk_enable(msm_uport->clk); + + /* Enable DELTA_CTS Interrupt */ + msm_uport->imr_reg |= UARTDM_ISR_DELTA_CTS_BMSK; + msm_hs_write(uport, UARTDM_IMR_ADDR, msm_uport->imr_reg); + + clk_disable(msm_uport->clk); + +} + +/* + * Standard API, Break Signal + * + * Control the transmission of a break signal. ctl eq 0 => break + * signal terminate ctl ne 0 => start break signal + */ +static void msm_hs_break_ctl(struct uart_port *uport, int ctl) +{ + struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport); + + clk_enable(msm_uport->clk); + msm_hs_write(uport, UARTDM_CR_ADDR, ctl ? START_BREAK : STOP_BREAK); + clk_disable(msm_uport->clk); +} + +static void msm_hs_config_port(struct uart_port *uport, int cfg_flags) +{ + unsigned long flags; + + spin_lock_irqsave(&uport->lock, flags); + if (cfg_flags & UART_CONFIG_TYPE) { + uport->type = PORT_MSM; + msm_hs_request_port(uport); + } + spin_unlock_irqrestore(&uport->lock, flags); +} + +/* Handle CTS changes (Called from interrupt handler) */ +static void msm_hs_handle_delta_cts(struct uart_port *uport) +{ + unsigned long flags; + struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport); + + spin_lock_irqsave(&uport->lock, flags); + clk_enable(msm_uport->clk); + + /* clear interrupt */ + msm_hs_write(uport, UARTDM_CR_ADDR, RESET_CTS); + uport->icount.cts++; + + clk_disable(msm_uport->clk); + spin_unlock_irqrestore(&uport->lock, flags); + + /* clear the IOCTL TIOCMIWAIT if called */ + wake_up_interruptible(&uport->state->port.delta_msr_wait); +} + +/* check if the TX path is flushed, and if so clock off + * returns 0 did not clock off, need to retry (still sending final byte) + * -1 did not clock off, do not retry + * 1 if we clocked off + */ +static int msm_hs_check_clock_off_locked(struct uart_port *uport) +{ + unsigned long sr_status; + struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport); + struct circ_buf *tx_buf = &uport->state->xmit; + + /* Cancel if tx tty buffer is not empty, dma is in flight, + * or tx fifo is not empty, or rx fifo is not empty */ + if (msm_uport->clk_state != MSM_HS_CLK_REQUEST_OFF || + !uart_circ_empty(tx_buf) || msm_uport->tx.dma_in_flight || + (msm_uport->imr_reg & UARTDM_ISR_TXLEV_BMSK) || + !(msm_uport->imr_reg & UARTDM_ISR_RXLEV_BMSK)) { + return -1; + } + + /* Make sure the uart is finished with the last byte */ + sr_status = msm_hs_read(uport, UARTDM_SR_ADDR); + if (!(sr_status & UARTDM_SR_TXEMT_BMSK)) + return 0; /* retry */ + + /* Make sure forced RXSTALE flush complete */ + switch (msm_uport->clk_req_off_state) { + case CLK_REQ_OFF_START: + msm_uport->clk_req_off_state = CLK_REQ_OFF_RXSTALE_ISSUED; + msm_hs_write(uport, UARTDM_CR_ADDR, FORCE_STALE_EVENT); + return 0; /* RXSTALE flush not complete - retry */ + case CLK_REQ_OFF_RXSTALE_ISSUED: + case CLK_REQ_OFF_FLUSH_ISSUED: + return 0; /* RXSTALE flush not complete - retry */ + case CLK_REQ_OFF_RXSTALE_FLUSHED: + break; /* continue */ + } + + if (msm_uport->rx.flush != FLUSH_SHUTDOWN) { + if (msm_uport->rx.flush == FLUSH_NONE) + msm_hs_stop_rx_locked(uport); + return 0; /* come back later to really clock off */ + } + + /* we really want to clock off */ + clk_disable(msm_uport->clk); + msm_uport->clk_state = MSM_HS_CLK_OFF; + + if (use_low_power_rx_wakeup(msm_uport)) { + msm_uport->rx_wakeup.ignore = 1; + enable_irq(msm_uport->rx_wakeup.irq); + } + return 1; +} + +static enum hrtimer_restart msm_hs_clk_off_retry(struct hrtimer *timer) +{ + unsigned long flags; + int ret = HRTIMER_NORESTART; + struct msm_hs_port *msm_uport = container_of(timer, struct msm_hs_port, + clk_off_timer); + struct uart_port *uport = &msm_uport->uport; + + spin_lock_irqsave(&uport->lock, flags); + + if (!msm_hs_check_clock_off_locked(uport)) { + hrtimer_forward_now(timer, msm_uport->clk_off_delay); + ret = HRTIMER_RESTART; + } + + spin_unlock_irqrestore(&uport->lock, flags); + + return ret; +} + +static irqreturn_t msm_hs_isr(int irq, void *dev) +{ + unsigned long flags; + unsigned long isr_status; + struct msm_hs_port *msm_uport = dev; + struct uart_port *uport = &msm_uport->uport; + struct circ_buf *tx_buf = &uport->state->xmit; + struct msm_hs_tx *tx = &msm_uport->tx; + struct msm_hs_rx *rx = &msm_uport->rx; + + spin_lock_irqsave(&uport->lock, flags); + + isr_status = msm_hs_read(uport, UARTDM_MISR_ADDR); + + /* Uart RX starting */ + if (isr_status & UARTDM_ISR_RXLEV_BMSK) { + msm_uport->imr_reg &= ~UARTDM_ISR_RXLEV_BMSK; + msm_hs_write(uport, UARTDM_IMR_ADDR, msm_uport->imr_reg); + } + /* Stale rx interrupt */ + if (isr_status & UARTDM_ISR_RXSTALE_BMSK) { + msm_hs_write(uport, UARTDM_CR_ADDR, STALE_EVENT_DISABLE); + msm_hs_write(uport, UARTDM_CR_ADDR, RESET_STALE_INT); + + if (msm_uport->clk_req_off_state == CLK_REQ_OFF_RXSTALE_ISSUED) + msm_uport->clk_req_off_state = + CLK_REQ_OFF_FLUSH_ISSUED; + if (rx->flush == FLUSH_NONE) { + rx->flush = FLUSH_DATA_READY; + msm_dmov_stop_cmd(msm_uport->dma_rx_channel, NULL, 1); + } + } + /* tx ready interrupt */ + if (isr_status & UARTDM_ISR_TX_READY_BMSK) { + /* Clear TX Ready */ + msm_hs_write(uport, UARTDM_CR_ADDR, CLEAR_TX_READY); + + if (msm_uport->clk_state == MSM_HS_CLK_REQUEST_OFF) { + msm_uport->imr_reg |= UARTDM_ISR_TXLEV_BMSK; + msm_hs_write(uport, UARTDM_IMR_ADDR, + msm_uport->imr_reg); + } + + /* Complete DMA TX transactions and submit new transactions */ + tx_buf->tail = (tx_buf->tail + tx->tx_count) & ~UART_XMIT_SIZE; + + tx->dma_in_flight = 0; + + uport->icount.tx += tx->tx_count; + if (tx->tx_ready_int_en) + msm_hs_submit_tx_locked(uport); + + if (uart_circ_chars_pending(tx_buf) < WAKEUP_CHARS) + uart_write_wakeup(uport); + } + if (isr_status & UARTDM_ISR_TXLEV_BMSK) { + /* TX FIFO is empty */ + msm_uport->imr_reg &= ~UARTDM_ISR_TXLEV_BMSK; + msm_hs_write(uport, UARTDM_IMR_ADDR, msm_uport->imr_reg); + if (!msm_hs_check_clock_off_locked(uport)) + hrtimer_start(&msm_uport->clk_off_timer, + msm_uport->clk_off_delay, + HRTIMER_MODE_REL); + } + + /* Change in CTS interrupt */ + if (isr_status & UARTDM_ISR_DELTA_CTS_BMSK) + msm_hs_handle_delta_cts(uport); + + spin_unlock_irqrestore(&uport->lock, flags); + + return IRQ_HANDLED; +} + +void msm_hs_request_clock_off_locked(struct uart_port *uport) +{ + struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport); + + if (msm_uport->clk_state == MSM_HS_CLK_ON) { + msm_uport->clk_state = MSM_HS_CLK_REQUEST_OFF; + msm_uport->clk_req_off_state = CLK_REQ_OFF_START; + if (!use_low_power_rx_wakeup(msm_uport)) + set_rfr_locked(uport, 0); + msm_uport->imr_reg |= UARTDM_ISR_TXLEV_BMSK; + msm_hs_write(uport, UARTDM_IMR_ADDR, msm_uport->imr_reg); + } +} + +/** + * msm_hs_request_clock_off - request to (i.e. asynchronously) turn off uart + * clock once pending TX is flushed and Rx DMA command is terminated. + * @uport: uart_port structure for the device instance. + * + * This functions puts the device into a partially active low power mode. It + * waits to complete all pending tx transactions, flushes ongoing Rx DMA + * command and terminates UART side Rx transaction, puts UART HW in non DMA + * mode and then clocks off the device. A client calls this when no UART + * data is expected. msm_request_clock_on() must be called before any further + * UART can be sent or received. + */ +void msm_hs_request_clock_off(struct uart_port *uport) +{ + unsigned long flags; + + spin_lock_irqsave(&uport->lock, flags); + msm_hs_request_clock_off_locked(uport); + spin_unlock_irqrestore(&uport->lock, flags); +} + +void msm_hs_request_clock_on_locked(struct uart_port *uport) +{ + struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport); + unsigned int data; + + switch (msm_uport->clk_state) { + case MSM_HS_CLK_OFF: + clk_enable(msm_uport->clk); + disable_irq_nosync(msm_uport->rx_wakeup.irq); + /* fall-through */ + case MSM_HS_CLK_REQUEST_OFF: + if (msm_uport->rx.flush == FLUSH_STOP || + msm_uport->rx.flush == FLUSH_SHUTDOWN) { + msm_hs_write(uport, UARTDM_CR_ADDR, RESET_RX); + data = msm_hs_read(uport, UARTDM_DMEN_ADDR); + data |= UARTDM_RX_DM_EN_BMSK; + msm_hs_write(uport, UARTDM_DMEN_ADDR, data); + } + hrtimer_try_to_cancel(&msm_uport->clk_off_timer); + if (msm_uport->rx.flush == FLUSH_SHUTDOWN) + msm_hs_start_rx_locked(uport); + if (!use_low_power_rx_wakeup(msm_uport)) + set_rfr_locked(uport, 1); + if (msm_uport->rx.flush == FLUSH_STOP) + msm_uport->rx.flush = FLUSH_IGNORE; + msm_uport->clk_state = MSM_HS_CLK_ON; + break; + case MSM_HS_CLK_ON: + break; + case MSM_HS_CLK_PORT_OFF: + break; + } +} + +/** + * msm_hs_request_clock_on - Switch the device from partially active low + * power mode to fully active (i.e. clock on) mode. + * @uport: uart_port structure for the device. + * + * This function switches on the input clock, puts UART HW into DMA mode + * and enqueues an Rx DMA command if the device was in partially active + * mode. It has no effect if called with the device in inactive state. + */ +void msm_hs_request_clock_on(struct uart_port *uport) +{ + unsigned long flags; + + spin_lock_irqsave(&uport->lock, flags); + msm_hs_request_clock_on_locked(uport); + spin_unlock_irqrestore(&uport->lock, flags); +} + +static irqreturn_t msm_hs_rx_wakeup_isr(int irq, void *dev) +{ + unsigned int wakeup = 0; + unsigned long flags; + struct msm_hs_port *msm_uport = dev; + struct uart_port *uport = &msm_uport->uport; + struct tty_struct *tty = NULL; + + spin_lock_irqsave(&uport->lock, flags); + if (msm_uport->clk_state == MSM_HS_CLK_OFF) { + /* ignore the first irq - it is a pending irq that occured + * before enable_irq() */ + if (msm_uport->rx_wakeup.ignore) + msm_uport->rx_wakeup.ignore = 0; + else + wakeup = 1; + } + + if (wakeup) { + /* the uart was clocked off during an rx, wake up and + * optionally inject char into tty rx */ + msm_hs_request_clock_on_locked(uport); + if (msm_uport->rx_wakeup.inject_rx) { + tty = uport->state->port.tty; + tty_insert_flip_char(tty, + msm_uport->rx_wakeup.rx_to_inject, + TTY_NORMAL); + queue_work(msm_hs_workqueue, &msm_uport->rx.tty_work); + } + } + + spin_unlock_irqrestore(&uport->lock, flags); + + return IRQ_HANDLED; +} + +static const char *msm_hs_type(struct uart_port *port) +{ + return (port->type == PORT_MSM) ? "MSM_HS_UART" : NULL; +} + +/* Called when port is opened */ +static int msm_hs_startup(struct uart_port *uport) +{ + int ret; + int rfr_level; + unsigned long flags; + unsigned int data; + struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport); + struct circ_buf *tx_buf = &uport->state->xmit; + struct msm_hs_tx *tx = &msm_uport->tx; + struct msm_hs_rx *rx = &msm_uport->rx; + + rfr_level = uport->fifosize; + if (rfr_level > 16) + rfr_level -= 16; + + tx->dma_base = dma_map_single(uport->dev, tx_buf->buf, UART_XMIT_SIZE, + DMA_TO_DEVICE); + + /* do not let tty layer execute RX in global workqueue, use a + * dedicated workqueue managed by this driver */ + uport->state->port.tty->low_latency = 1; + + /* turn on uart clk */ + ret = msm_hs_init_clk_locked(uport); + if (unlikely(ret)) { + printk(KERN_ERR "Turning uartclk failed!\n"); + goto err_msm_hs_init_clk; + } + + /* Set auto RFR Level */ + data = msm_hs_read(uport, UARTDM_MR1_ADDR); + data &= ~UARTDM_MR1_AUTO_RFR_LEVEL1_BMSK; + data &= ~UARTDM_MR1_AUTO_RFR_LEVEL0_BMSK; + data |= (UARTDM_MR1_AUTO_RFR_LEVEL1_BMSK & (rfr_level << 2)); + data |= (UARTDM_MR1_AUTO_RFR_LEVEL0_BMSK & rfr_level); + msm_hs_write(uport, UARTDM_MR1_ADDR, data); + + /* Make sure RXSTALE count is non-zero */ + data = msm_hs_read(uport, UARTDM_IPR_ADDR); + if (!data) { + data |= 0x1f & UARTDM_IPR_STALE_LSB_BMSK; + msm_hs_write(uport, UARTDM_IPR_ADDR, data); + } + + /* Enable Data Mover Mode */ + data = UARTDM_TX_DM_EN_BMSK | UARTDM_RX_DM_EN_BMSK; + msm_hs_write(uport, UARTDM_DMEN_ADDR, data); + + /* Reset TX */ + msm_hs_write(uport, UARTDM_CR_ADDR, RESET_TX); + msm_hs_write(uport, UARTDM_CR_ADDR, RESET_RX); + msm_hs_write(uport, UARTDM_CR_ADDR, RESET_ERROR_STATUS); + msm_hs_write(uport, UARTDM_CR_ADDR, RESET_BREAK_INT); + msm_hs_write(uport, UARTDM_CR_ADDR, RESET_STALE_INT); + msm_hs_write(uport, UARTDM_CR_ADDR, RESET_CTS); + msm_hs_write(uport, UARTDM_CR_ADDR, RFR_LOW); + /* Turn on Uart Receiver */ + msm_hs_write(uport, UARTDM_CR_ADDR, UARTDM_CR_RX_EN_BMSK); + + /* Turn on Uart Transmitter */ + msm_hs_write(uport, UARTDM_CR_ADDR, UARTDM_CR_TX_EN_BMSK); + + /* Initialize the tx */ + tx->tx_ready_int_en = 0; + tx->dma_in_flight = 0; + + tx->xfer.complete_func = msm_hs_dmov_tx_callback; + tx->xfer.execute_func = NULL; + + tx->command_ptr->cmd = CMD_LC | + CMD_DST_CRCI(msm_uport->dma_tx_crci) | CMD_MODE_BOX; + + tx->command_ptr->src_dst_len = (MSM_UARTDM_BURST_SIZE << 16) + | (MSM_UARTDM_BURST_SIZE); + + tx->command_ptr->row_offset = (MSM_UARTDM_BURST_SIZE << 16); + + tx->command_ptr->dst_row_addr = + msm_uport->uport.mapbase + UARTDM_TF_ADDR; + + + /* Turn on Uart Receive */ + rx->xfer.complete_func = msm_hs_dmov_rx_callback; + rx->xfer.execute_func = NULL; + + rx->command_ptr->cmd = CMD_LC | + CMD_SRC_CRCI(msm_uport->dma_rx_crci) | CMD_MODE_BOX; + + rx->command_ptr->src_dst_len = (MSM_UARTDM_BURST_SIZE << 16) + | (MSM_UARTDM_BURST_SIZE); + rx->command_ptr->row_offset = MSM_UARTDM_BURST_SIZE; + rx->command_ptr->src_row_addr = uport->mapbase + UARTDM_RF_ADDR; + + + msm_uport->imr_reg |= UARTDM_ISR_RXSTALE_BMSK; + /* Enable reading the current CTS, no harm even if CTS is ignored */ + msm_uport->imr_reg |= UARTDM_ISR_CURRENT_CTS_BMSK; + + msm_hs_write(uport, UARTDM_TFWR_ADDR, 0); /* TXLEV on empty TX fifo */ + + + ret = request_irq(uport->irq, msm_hs_isr, IRQF_TRIGGER_HIGH, + "msm_hs_uart", msm_uport); + if (unlikely(ret)) { + printk(KERN_ERR "Request msm_hs_uart IRQ failed!\n"); + goto err_request_irq; + } + if (use_low_power_rx_wakeup(msm_uport)) { + ret = request_irq(msm_uport->rx_wakeup.irq, + msm_hs_rx_wakeup_isr, + IRQF_TRIGGER_FALLING, + "msm_hs_rx_wakeup", msm_uport); + if (unlikely(ret)) { + printk(KERN_ERR "Request msm_hs_rx_wakeup IRQ failed!\n"); + free_irq(uport->irq, msm_uport); + goto err_request_irq; + } + disable_irq(msm_uport->rx_wakeup.irq); + } + + spin_lock_irqsave(&uport->lock, flags); + + msm_hs_write(uport, UARTDM_RFWR_ADDR, 0); + msm_hs_start_rx_locked(uport); + + spin_unlock_irqrestore(&uport->lock, flags); + ret = pm_runtime_set_active(uport->dev); + if (ret) + dev_err(uport->dev, "set active error:%d\n", ret); + pm_runtime_enable(uport->dev); + + return 0; + +err_request_irq: +err_msm_hs_init_clk: + dma_unmap_single(uport->dev, tx->dma_base, + UART_XMIT_SIZE, DMA_TO_DEVICE); + return ret; +} + +/* Initialize tx and rx data structures */ +static int __devinit uartdm_init_port(struct uart_port *uport) +{ + int ret = 0; + struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport); + struct msm_hs_tx *tx = &msm_uport->tx; + struct msm_hs_rx *rx = &msm_uport->rx; + + /* Allocate the command pointer. Needs to be 64 bit aligned */ + tx->command_ptr = kmalloc(sizeof(dmov_box), GFP_KERNEL | __GFP_DMA); + if (!tx->command_ptr) + return -ENOMEM; + + tx->command_ptr_ptr = kmalloc(sizeof(u32 *), GFP_KERNEL | __GFP_DMA); + if (!tx->command_ptr_ptr) { + ret = -ENOMEM; + goto err_tx_command_ptr_ptr; + } + + tx->mapped_cmd_ptr = dma_map_single(uport->dev, tx->command_ptr, + sizeof(dmov_box), DMA_TO_DEVICE); + tx->mapped_cmd_ptr_ptr = dma_map_single(uport->dev, + tx->command_ptr_ptr, + sizeof(u32 *), DMA_TO_DEVICE); + tx->xfer.cmdptr = DMOV_CMD_ADDR(tx->mapped_cmd_ptr_ptr); + + init_waitqueue_head(&rx->wait); + + rx->pool = dma_pool_create("rx_buffer_pool", uport->dev, + UARTDM_RX_BUF_SIZE, 16, 0); + if (!rx->pool) { + pr_err("%s(): cannot allocate rx_buffer_pool", __func__); + ret = -ENOMEM; + goto err_dma_pool_create; + } + + rx->buffer = dma_pool_alloc(rx->pool, GFP_KERNEL, &rx->rbuffer); + if (!rx->buffer) { + pr_err("%s(): cannot allocate rx->buffer", __func__); + ret = -ENOMEM; + goto err_dma_pool_alloc; + } + + /* Allocate the command pointer. Needs to be 64 bit aligned */ + rx->command_ptr = kmalloc(sizeof(dmov_box), GFP_KERNEL | __GFP_DMA); + if (!rx->command_ptr) { + pr_err("%s(): cannot allocate rx->command_ptr", __func__); + ret = -ENOMEM; + goto err_rx_command_ptr; + } + + rx->command_ptr_ptr = kmalloc(sizeof(u32 *), GFP_KERNEL | __GFP_DMA); + if (!rx->command_ptr_ptr) { + pr_err("%s(): cannot allocate rx->command_ptr_ptr", __func__); + ret = -ENOMEM; + goto err_rx_command_ptr_ptr; + } + + rx->command_ptr->num_rows = ((UARTDM_RX_BUF_SIZE >> 4) << 16) | + (UARTDM_RX_BUF_SIZE >> 4); + + rx->command_ptr->dst_row_addr = rx->rbuffer; + + rx->mapped_cmd_ptr = dma_map_single(uport->dev, rx->command_ptr, + sizeof(dmov_box), DMA_TO_DEVICE); + + *rx->command_ptr_ptr = CMD_PTR_LP | DMOV_CMD_ADDR(rx->mapped_cmd_ptr); + + rx->cmdptr_dmaaddr = dma_map_single(uport->dev, rx->command_ptr_ptr, + sizeof(u32 *), DMA_TO_DEVICE); + rx->xfer.cmdptr = DMOV_CMD_ADDR(rx->cmdptr_dmaaddr); + + INIT_WORK(&rx->tty_work, msm_hs_tty_flip_buffer_work); + + return ret; + +err_rx_command_ptr_ptr: + kfree(rx->command_ptr); +err_rx_command_ptr: + dma_pool_free(msm_uport->rx.pool, msm_uport->rx.buffer, + msm_uport->rx.rbuffer); +err_dma_pool_alloc: + dma_pool_destroy(msm_uport->rx.pool); +err_dma_pool_create: + dma_unmap_single(uport->dev, msm_uport->tx.mapped_cmd_ptr_ptr, + sizeof(u32 *), DMA_TO_DEVICE); + dma_unmap_single(uport->dev, msm_uport->tx.mapped_cmd_ptr, + sizeof(dmov_box), DMA_TO_DEVICE); + kfree(msm_uport->tx.command_ptr_ptr); +err_tx_command_ptr_ptr: + kfree(msm_uport->tx.command_ptr); + return ret; +} + +static int __devinit msm_hs_probe(struct platform_device *pdev) +{ + int ret; + struct uart_port *uport; + struct msm_hs_port *msm_uport; + struct resource *resource; + const struct msm_serial_hs_platform_data *pdata = + pdev->dev.platform_data; + + if (pdev->id < 0 || pdev->id >= UARTDM_NR) { + printk(KERN_ERR "Invalid plaform device ID = %d\n", pdev->id); + return -EINVAL; + } + + msm_uport = &q_uart_port[pdev->id]; + uport = &msm_uport->uport; + + uport->dev = &pdev->dev; + + resource = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (unlikely(!resource)) + return -ENXIO; + + uport->mapbase = resource->start; + uport->irq = platform_get_irq(pdev, 0); + if (unlikely(uport->irq < 0)) + return -ENXIO; + + if (unlikely(set_irq_wake(uport->irq, 1))) + return -ENXIO; + + if (pdata == NULL || pdata->rx_wakeup_irq < 0) + msm_uport->rx_wakeup.irq = -1; + else { + msm_uport->rx_wakeup.irq = pdata->rx_wakeup_irq; + msm_uport->rx_wakeup.ignore = 1; + msm_uport->rx_wakeup.inject_rx = pdata->inject_rx_on_wakeup; + msm_uport->rx_wakeup.rx_to_inject = pdata->rx_to_inject; + + if (unlikely(msm_uport->rx_wakeup.irq < 0)) + return -ENXIO; + + if (unlikely(set_irq_wake(msm_uport->rx_wakeup.irq, 1))) + return -ENXIO; + } + + if (pdata == NULL) + msm_uport->exit_lpm_cb = NULL; + else + msm_uport->exit_lpm_cb = pdata->exit_lpm_cb; + + resource = platform_get_resource_byname(pdev, IORESOURCE_DMA, + "uartdm_channels"); + if (unlikely(!resource)) + return -ENXIO; + + msm_uport->dma_tx_channel = resource->start; + msm_uport->dma_rx_channel = resource->end; + + resource = platform_get_resource_byname(pdev, IORESOURCE_DMA, + "uartdm_crci"); + if (unlikely(!resource)) + return -ENXIO; + + msm_uport->dma_tx_crci = resource->start; + msm_uport->dma_rx_crci = resource->end; + + uport->iotype = UPIO_MEM; + uport->fifosize = UART_FIFOSIZE; + uport->ops = &msm_hs_ops; + uport->flags = UPF_BOOT_AUTOCONF; + uport->uartclk = UARTCLK; + msm_uport->imr_reg = 0x0; + msm_uport->clk = clk_get(&pdev->dev, "uartdm_clk"); + if (IS_ERR(msm_uport->clk)) + return PTR_ERR(msm_uport->clk); + + ret = uartdm_init_port(uport); + if (unlikely(ret)) + return ret; + + msm_uport->clk_state = MSM_HS_CLK_PORT_OFF; + hrtimer_init(&msm_uport->clk_off_timer, CLOCK_MONOTONIC, + HRTIMER_MODE_REL); + msm_uport->clk_off_timer.function = msm_hs_clk_off_retry; + msm_uport->clk_off_delay = ktime_set(0, 1000000); /* 1ms */ + + uport->line = pdev->id; + return uart_add_one_port(&msm_hs_driver, uport); +} + +static int __init msm_serial_hs_init(void) +{ + int ret, i; + + /* Init all UARTS as non-configured */ + for (i = 0; i < UARTDM_NR; i++) + q_uart_port[i].uport.type = PORT_UNKNOWN; + + msm_hs_workqueue = create_singlethread_workqueue("msm_serial_hs"); + if (unlikely(!msm_hs_workqueue)) + return -ENOMEM; + + ret = uart_register_driver(&msm_hs_driver); + if (unlikely(ret)) { + printk(KERN_ERR "%s failed to load\n", __func__); + goto err_uart_register_driver; + } + + ret = platform_driver_register(&msm_serial_hs_platform_driver); + if (ret) { + printk(KERN_ERR "%s failed to load\n", __func__); + goto err_platform_driver_register; + } + + return ret; + +err_platform_driver_register: + uart_unregister_driver(&msm_hs_driver); +err_uart_register_driver: + destroy_workqueue(msm_hs_workqueue); + return ret; +} +module_init(msm_serial_hs_init); + +/* + * Called by the upper layer when port is closed. + * - Disables the port + * - Unhook the ISR + */ +static void msm_hs_shutdown(struct uart_port *uport) +{ + unsigned long flags; + struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport); + + BUG_ON(msm_uport->rx.flush < FLUSH_STOP); + + spin_lock_irqsave(&uport->lock, flags); + clk_enable(msm_uport->clk); + + /* Disable the transmitter */ + msm_hs_write(uport, UARTDM_CR_ADDR, UARTDM_CR_TX_DISABLE_BMSK); + /* Disable the receiver */ + msm_hs_write(uport, UARTDM_CR_ADDR, UARTDM_CR_RX_DISABLE_BMSK); + + pm_runtime_disable(uport->dev); + pm_runtime_set_suspended(uport->dev); + + /* Free the interrupt */ + free_irq(uport->irq, msm_uport); + if (use_low_power_rx_wakeup(msm_uport)) + free_irq(msm_uport->rx_wakeup.irq, msm_uport); + + msm_uport->imr_reg = 0; + msm_hs_write(uport, UARTDM_IMR_ADDR, msm_uport->imr_reg); + + wait_event(msm_uport->rx.wait, msm_uport->rx.flush == FLUSH_SHUTDOWN); + + clk_disable(msm_uport->clk); /* to balance local clk_enable() */ + if (msm_uport->clk_state != MSM_HS_CLK_OFF) + clk_disable(msm_uport->clk); /* to balance clk_state */ + msm_uport->clk_state = MSM_HS_CLK_PORT_OFF; + + dma_unmap_single(uport->dev, msm_uport->tx.dma_base, + UART_XMIT_SIZE, DMA_TO_DEVICE); + + spin_unlock_irqrestore(&uport->lock, flags); + + if (cancel_work_sync(&msm_uport->rx.tty_work)) + msm_hs_tty_flip_buffer_work(&msm_uport->rx.tty_work); +} + +static void __exit msm_serial_hs_exit(void) +{ + flush_workqueue(msm_hs_workqueue); + destroy_workqueue(msm_hs_workqueue); + platform_driver_unregister(&msm_serial_hs_platform_driver); + uart_unregister_driver(&msm_hs_driver); +} +module_exit(msm_serial_hs_exit); + +#ifdef CONFIG_PM_RUNTIME +static int msm_hs_runtime_idle(struct device *dev) +{ + /* + * returning success from idle results in runtime suspend to be + * called + */ + return 0; +} + +static int msm_hs_runtime_resume(struct device *dev) +{ + struct platform_device *pdev = container_of(dev, struct + platform_device, dev); + struct msm_hs_port *msm_uport = &q_uart_port[pdev->id]; + + msm_hs_request_clock_on(&msm_uport->uport); + return 0; +} + +static int msm_hs_runtime_suspend(struct device *dev) +{ + struct platform_device *pdev = container_of(dev, struct + platform_device, dev); + struct msm_hs_port *msm_uport = &q_uart_port[pdev->id]; + + msm_hs_request_clock_off(&msm_uport->uport); + return 0; +} +#else +#define msm_hs_runtime_idle NULL +#define msm_hs_runtime_resume NULL +#define msm_hs_runtime_suspend NULL +#endif + +static const struct dev_pm_ops msm_hs_dev_pm_ops = { + .runtime_suspend = msm_hs_runtime_suspend, + .runtime_resume = msm_hs_runtime_resume, + .runtime_idle = msm_hs_runtime_idle, +}; + +static struct platform_driver msm_serial_hs_platform_driver = { + .probe = msm_hs_probe, + .remove = __devexit_p(msm_hs_remove), + .driver = { + .name = "msm_serial_hs", + .owner = THIS_MODULE, + .pm = &msm_hs_dev_pm_ops, + }, +}; + +static struct uart_driver msm_hs_driver = { + .owner = THIS_MODULE, + .driver_name = "msm_serial_hs", + .dev_name = "ttyHS", + .nr = UARTDM_NR, + .cons = 0, +}; + +static struct uart_ops msm_hs_ops = { + .tx_empty = msm_hs_tx_empty, + .set_mctrl = msm_hs_set_mctrl_locked, + .get_mctrl = msm_hs_get_mctrl_locked, + .stop_tx = msm_hs_stop_tx_locked, + .start_tx = msm_hs_start_tx_locked, + .stop_rx = msm_hs_stop_rx_locked, + .enable_ms = msm_hs_enable_ms_locked, + .break_ctl = msm_hs_break_ctl, + .startup = msm_hs_startup, + .shutdown = msm_hs_shutdown, + .set_termios = msm_hs_set_termios, + .pm = msm_hs_pm, + .type = msm_hs_type, + .config_port = msm_hs_config_port, + .release_port = msm_hs_release_port, + .request_port = msm_hs_request_port, +}; + +MODULE_DESCRIPTION("High Speed UART Driver for the MSM chipset"); +MODULE_VERSION("1.2"); +MODULE_LICENSE("GPL v2"); |
