diff options
Diffstat (limited to 'drivers/dma/tegra20-apb-dma.c')
| -rw-r--r-- | drivers/dma/tegra20-apb-dma.c | 1415 |
1 files changed, 1415 insertions, 0 deletions
diff --git a/drivers/dma/tegra20-apb-dma.c b/drivers/dma/tegra20-apb-dma.c new file mode 100644 index 000000000000..d52dbc6c54ab --- /dev/null +++ b/drivers/dma/tegra20-apb-dma.c @@ -0,0 +1,1415 @@ +/* + * DMA driver for Nvidia's Tegra20 APB DMA controller. + * + * Copyright (c) 2012, NVIDIA CORPORATION. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope 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. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <linux/bitops.h> +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/dmaengine.h> +#include <linux/dma-mapping.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/mm.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/slab.h> + +#include <mach/clk.h> +#include "dmaengine.h" + +#define TEGRA_APBDMA_GENERAL 0x0 +#define TEGRA_APBDMA_GENERAL_ENABLE BIT(31) + +#define TEGRA_APBDMA_CONTROL 0x010 +#define TEGRA_APBDMA_IRQ_MASK 0x01c +#define TEGRA_APBDMA_IRQ_MASK_SET 0x020 + +/* CSR register */ +#define TEGRA_APBDMA_CHAN_CSR 0x00 +#define TEGRA_APBDMA_CSR_ENB BIT(31) +#define TEGRA_APBDMA_CSR_IE_EOC BIT(30) +#define TEGRA_APBDMA_CSR_HOLD BIT(29) +#define TEGRA_APBDMA_CSR_DIR BIT(28) +#define TEGRA_APBDMA_CSR_ONCE BIT(27) +#define TEGRA_APBDMA_CSR_FLOW BIT(21) +#define TEGRA_APBDMA_CSR_REQ_SEL_SHIFT 16 +#define TEGRA_APBDMA_CSR_WCOUNT_MASK 0xFFFC + +/* STATUS register */ +#define TEGRA_APBDMA_CHAN_STATUS 0x004 +#define TEGRA_APBDMA_STATUS_BUSY BIT(31) +#define TEGRA_APBDMA_STATUS_ISE_EOC BIT(30) +#define TEGRA_APBDMA_STATUS_HALT BIT(29) +#define TEGRA_APBDMA_STATUS_PING_PONG BIT(28) +#define TEGRA_APBDMA_STATUS_COUNT_SHIFT 2 +#define TEGRA_APBDMA_STATUS_COUNT_MASK 0xFFFC + +/* AHB memory address */ +#define TEGRA_APBDMA_CHAN_AHBPTR 0x010 + +/* AHB sequence register */ +#define TEGRA_APBDMA_CHAN_AHBSEQ 0x14 +#define TEGRA_APBDMA_AHBSEQ_INTR_ENB BIT(31) +#define TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_8 (0 << 28) +#define TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_16 (1 << 28) +#define TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_32 (2 << 28) +#define TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_64 (3 << 28) +#define TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_128 (4 << 28) +#define TEGRA_APBDMA_AHBSEQ_DATA_SWAP BIT(27) +#define TEGRA_APBDMA_AHBSEQ_BURST_1 (4 << 24) +#define TEGRA_APBDMA_AHBSEQ_BURST_4 (5 << 24) +#define TEGRA_APBDMA_AHBSEQ_BURST_8 (6 << 24) +#define TEGRA_APBDMA_AHBSEQ_DBL_BUF BIT(19) +#define TEGRA_APBDMA_AHBSEQ_WRAP_SHIFT 16 +#define TEGRA_APBDMA_AHBSEQ_WRAP_NONE 0 + +/* APB address */ +#define TEGRA_APBDMA_CHAN_APBPTR 0x018 + +/* APB sequence register */ +#define TEGRA_APBDMA_CHAN_APBSEQ 0x01c +#define TEGRA_APBDMA_APBSEQ_BUS_WIDTH_8 (0 << 28) +#define TEGRA_APBDMA_APBSEQ_BUS_WIDTH_16 (1 << 28) +#define TEGRA_APBDMA_APBSEQ_BUS_WIDTH_32 (2 << 28) +#define TEGRA_APBDMA_APBSEQ_BUS_WIDTH_64 (3 << 28) +#define TEGRA_APBDMA_APBSEQ_BUS_WIDTH_128 (4 << 28) +#define TEGRA_APBDMA_APBSEQ_DATA_SWAP BIT(27) +#define TEGRA_APBDMA_APBSEQ_WRAP_WORD_1 (1 << 16) + +/* + * If any burst is in flight and DMA paused then this is the time to complete + * on-flight burst and update DMA status register. + */ +#define TEGRA_APBDMA_BURST_COMPLETE_TIME 20 + +/* Channel base address offset from APBDMA base address */ +#define TEGRA_APBDMA_CHANNEL_BASE_ADD_OFFSET 0x1000 + +/* DMA channel register space size */ +#define TEGRA_APBDMA_CHANNEL_REGISTER_SIZE 0x20 + +struct tegra_dma; + +/* + * tegra_dma_chip_data Tegra chip specific DMA data + * @nr_channels: Number of channels available in the controller. + * @max_dma_count: Maximum DMA transfer count supported by DMA controller. + */ +struct tegra_dma_chip_data { + int nr_channels; + int max_dma_count; +}; + +/* DMA channel registers */ +struct tegra_dma_channel_regs { + unsigned long csr; + unsigned long ahb_ptr; + unsigned long apb_ptr; + unsigned long ahb_seq; + unsigned long apb_seq; +}; + +/* + * tegra_dma_sg_req: Dma request details to configure hardware. This + * contains the details for one transfer to configure DMA hw. + * The client's request for data transfer can be broken into multiple + * sub-transfer as per requester details and hw support. + * This sub transfer get added in the list of transfer and point to Tegra + * DMA descriptor which manages the transfer details. + */ +struct tegra_dma_sg_req { + struct tegra_dma_channel_regs ch_regs; + int req_len; + bool configured; + bool last_sg; + bool half_done; + struct list_head node; + struct tegra_dma_desc *dma_desc; +}; + +/* + * tegra_dma_desc: Tegra DMA descriptors which manages the client requests. + * This descriptor keep track of transfer status, callbacks and request + * counts etc. + */ +struct tegra_dma_desc { + struct dma_async_tx_descriptor txd; + int bytes_requested; + int bytes_transferred; + enum dma_status dma_status; + struct list_head node; + struct list_head tx_list; + struct list_head cb_node; + int cb_count; +}; + +struct tegra_dma_channel; + +typedef void (*dma_isr_handler)(struct tegra_dma_channel *tdc, + bool to_terminate); + +/* tegra_dma_channel: Channel specific information */ +struct tegra_dma_channel { + struct dma_chan dma_chan; + bool config_init; + int id; + int irq; + unsigned long chan_base_offset; + spinlock_t lock; + bool busy; + struct tegra_dma *tdma; + bool cyclic; + + /* Different lists for managing the requests */ + struct list_head free_sg_req; + struct list_head pending_sg_req; + struct list_head free_dma_desc; + struct list_head cb_desc; + + /* ISR handler and tasklet for bottom half of isr handling */ + dma_isr_handler isr_handler; + struct tasklet_struct tasklet; + dma_async_tx_callback callback; + void *callback_param; + + /* Channel-slave specific configuration */ + struct dma_slave_config dma_sconfig; +}; + +/* tegra_dma: Tegra DMA specific information */ +struct tegra_dma { + struct dma_device dma_dev; + struct device *dev; + struct clk *dma_clk; + spinlock_t global_lock; + void __iomem *base_addr; + struct tegra_dma_chip_data *chip_data; + + /* Some register need to be cache before suspend */ + u32 reg_gen; + + /* Last member of the structure */ + struct tegra_dma_channel channels[0]; +}; + +static inline void tdma_write(struct tegra_dma *tdma, u32 reg, u32 val) +{ + writel(val, tdma->base_addr + reg); +} + +static inline u32 tdma_read(struct tegra_dma *tdma, u32 reg) +{ + return readl(tdma->base_addr + reg); +} + +static inline void tdc_write(struct tegra_dma_channel *tdc, + u32 reg, u32 val) +{ + writel(val, tdc->tdma->base_addr + tdc->chan_base_offset + reg); +} + +static inline u32 tdc_read(struct tegra_dma_channel *tdc, u32 reg) +{ + return readl(tdc->tdma->base_addr + tdc->chan_base_offset + reg); +} + +static inline struct tegra_dma_channel *to_tegra_dma_chan(struct dma_chan *dc) +{ + return container_of(dc, struct tegra_dma_channel, dma_chan); +} + +static inline struct tegra_dma_desc *txd_to_tegra_dma_desc( + struct dma_async_tx_descriptor *td) +{ + return container_of(td, struct tegra_dma_desc, txd); +} + +static inline struct device *tdc2dev(struct tegra_dma_channel *tdc) +{ + return &tdc->dma_chan.dev->device; +} + +static dma_cookie_t tegra_dma_tx_submit(struct dma_async_tx_descriptor *tx); +static int tegra_dma_runtime_suspend(struct device *dev); +static int tegra_dma_runtime_resume(struct device *dev); + +/* Get DMA desc from free list, if not there then allocate it. */ +static struct tegra_dma_desc *tegra_dma_desc_get( + struct tegra_dma_channel *tdc) +{ + struct tegra_dma_desc *dma_desc; + unsigned long flags; + + spin_lock_irqsave(&tdc->lock, flags); + + /* Do not allocate if desc are waiting for ack */ + list_for_each_entry(dma_desc, &tdc->free_dma_desc, node) { + if (async_tx_test_ack(&dma_desc->txd)) { + list_del(&dma_desc->node); + spin_unlock_irqrestore(&tdc->lock, flags); + return dma_desc; + } + } + + spin_unlock_irqrestore(&tdc->lock, flags); + + /* Allocate DMA desc */ + dma_desc = kzalloc(sizeof(*dma_desc), GFP_ATOMIC); + if (!dma_desc) { + dev_err(tdc2dev(tdc), "dma_desc alloc failed\n"); + return NULL; + } + + dma_async_tx_descriptor_init(&dma_desc->txd, &tdc->dma_chan); + dma_desc->txd.tx_submit = tegra_dma_tx_submit; + dma_desc->txd.flags = 0; + return dma_desc; +} + +static void tegra_dma_desc_put(struct tegra_dma_channel *tdc, + struct tegra_dma_desc *dma_desc) +{ + unsigned long flags; + + spin_lock_irqsave(&tdc->lock, flags); + if (!list_empty(&dma_desc->tx_list)) + list_splice_init(&dma_desc->tx_list, &tdc->free_sg_req); + list_add_tail(&dma_desc->node, &tdc->free_dma_desc); + spin_unlock_irqrestore(&tdc->lock, flags); +} + +static struct tegra_dma_sg_req *tegra_dma_sg_req_get( + struct tegra_dma_channel *tdc) +{ + struct tegra_dma_sg_req *sg_req = NULL; + unsigned long flags; + + spin_lock_irqsave(&tdc->lock, flags); + if (!list_empty(&tdc->free_sg_req)) { + sg_req = list_first_entry(&tdc->free_sg_req, + typeof(*sg_req), node); + list_del(&sg_req->node); + spin_unlock_irqrestore(&tdc->lock, flags); + return sg_req; + } + spin_unlock_irqrestore(&tdc->lock, flags); + + sg_req = kzalloc(sizeof(struct tegra_dma_sg_req), GFP_ATOMIC); + if (!sg_req) + dev_err(tdc2dev(tdc), "sg_req alloc failed\n"); + return sg_req; +} + +static int tegra_dma_slave_config(struct dma_chan *dc, + struct dma_slave_config *sconfig) +{ + struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc); + + if (!list_empty(&tdc->pending_sg_req)) { + dev_err(tdc2dev(tdc), "Configuration not allowed\n"); + return -EBUSY; + } + + memcpy(&tdc->dma_sconfig, sconfig, sizeof(*sconfig)); + tdc->config_init = true; + return 0; +} + +static void tegra_dma_global_pause(struct tegra_dma_channel *tdc, + bool wait_for_burst_complete) +{ + struct tegra_dma *tdma = tdc->tdma; + + spin_lock(&tdma->global_lock); + tdma_write(tdma, TEGRA_APBDMA_GENERAL, 0); + if (wait_for_burst_complete) + udelay(TEGRA_APBDMA_BURST_COMPLETE_TIME); +} + +static void tegra_dma_global_resume(struct tegra_dma_channel *tdc) +{ + struct tegra_dma *tdma = tdc->tdma; + + tdma_write(tdma, TEGRA_APBDMA_GENERAL, TEGRA_APBDMA_GENERAL_ENABLE); + spin_unlock(&tdma->global_lock); +} + +static void tegra_dma_stop(struct tegra_dma_channel *tdc) +{ + u32 csr; + u32 status; + + /* Disable interrupts */ + csr = tdc_read(tdc, TEGRA_APBDMA_CHAN_CSR); + csr &= ~TEGRA_APBDMA_CSR_IE_EOC; + tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR, csr); + + /* Disable DMA */ + csr &= ~TEGRA_APBDMA_CSR_ENB; + tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR, csr); + + /* Clear interrupt status if it is there */ + status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS); + if (status & TEGRA_APBDMA_STATUS_ISE_EOC) { + dev_dbg(tdc2dev(tdc), "%s():clearing interrupt\n", __func__); + tdc_write(tdc, TEGRA_APBDMA_CHAN_STATUS, status); + } + tdc->busy = false; +} + +static void tegra_dma_start(struct tegra_dma_channel *tdc, + struct tegra_dma_sg_req *sg_req) +{ + struct tegra_dma_channel_regs *ch_regs = &sg_req->ch_regs; + + tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR, ch_regs->csr); + tdc_write(tdc, TEGRA_APBDMA_CHAN_APBSEQ, ch_regs->apb_seq); + tdc_write(tdc, TEGRA_APBDMA_CHAN_APBPTR, ch_regs->apb_ptr); + tdc_write(tdc, TEGRA_APBDMA_CHAN_AHBSEQ, ch_regs->ahb_seq); + tdc_write(tdc, TEGRA_APBDMA_CHAN_AHBPTR, ch_regs->ahb_ptr); + + /* Start DMA */ + tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR, + ch_regs->csr | TEGRA_APBDMA_CSR_ENB); +} + +static void tegra_dma_configure_for_next(struct tegra_dma_channel *tdc, + struct tegra_dma_sg_req *nsg_req) +{ + unsigned long status; + + /* + * The DMA controller reloads the new configuration for next transfer + * after last burst of current transfer completes. + * If there is no IEC status then this makes sure that last burst + * has not be completed. There may be case that last burst is on + * flight and so it can complete but because DMA is paused, it + * will not generates interrupt as well as not reload the new + * configuration. + * If there is already IEC status then interrupt handler need to + * load new configuration. + */ + tegra_dma_global_pause(tdc, false); + status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS); + + /* + * If interrupt is pending then do nothing as the ISR will handle + * the programing for new request. + */ + if (status & TEGRA_APBDMA_STATUS_ISE_EOC) { + dev_err(tdc2dev(tdc), + "Skipping new configuration as interrupt is pending\n"); + tegra_dma_global_resume(tdc); + return; + } + + /* Safe to program new configuration */ + tdc_write(tdc, TEGRA_APBDMA_CHAN_APBPTR, nsg_req->ch_regs.apb_ptr); + tdc_write(tdc, TEGRA_APBDMA_CHAN_AHBPTR, nsg_req->ch_regs.ahb_ptr); + tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR, + nsg_req->ch_regs.csr | TEGRA_APBDMA_CSR_ENB); + nsg_req->configured = true; + + tegra_dma_global_resume(tdc); +} + +static void tdc_start_head_req(struct tegra_dma_channel *tdc) +{ + struct tegra_dma_sg_req *sg_req; + + if (list_empty(&tdc->pending_sg_req)) + return; + + sg_req = list_first_entry(&tdc->pending_sg_req, + typeof(*sg_req), node); + tegra_dma_start(tdc, sg_req); + sg_req->configured = true; + tdc->busy = true; +} + +static void tdc_configure_next_head_desc(struct tegra_dma_channel *tdc) +{ + struct tegra_dma_sg_req *hsgreq; + struct tegra_dma_sg_req *hnsgreq; + + if (list_empty(&tdc->pending_sg_req)) + return; + + hsgreq = list_first_entry(&tdc->pending_sg_req, typeof(*hsgreq), node); + if (!list_is_last(&hsgreq->node, &tdc->pending_sg_req)) { + hnsgreq = list_first_entry(&hsgreq->node, + typeof(*hnsgreq), node); + tegra_dma_configure_for_next(tdc, hnsgreq); + } +} + +static inline int get_current_xferred_count(struct tegra_dma_channel *tdc, + struct tegra_dma_sg_req *sg_req, unsigned long status) +{ + return sg_req->req_len - (status & TEGRA_APBDMA_STATUS_COUNT_MASK) - 4; +} + +static void tegra_dma_abort_all(struct tegra_dma_channel *tdc) +{ + struct tegra_dma_sg_req *sgreq; + struct tegra_dma_desc *dma_desc; + + while (!list_empty(&tdc->pending_sg_req)) { + sgreq = list_first_entry(&tdc->pending_sg_req, + typeof(*sgreq), node); + list_del(&sgreq->node); + list_add_tail(&sgreq->node, &tdc->free_sg_req); + if (sgreq->last_sg) { + dma_desc = sgreq->dma_desc; + dma_desc->dma_status = DMA_ERROR; + list_add_tail(&dma_desc->node, &tdc->free_dma_desc); + + /* Add in cb list if it is not there. */ + if (!dma_desc->cb_count) + list_add_tail(&dma_desc->cb_node, + &tdc->cb_desc); + dma_desc->cb_count++; + } + } + tdc->isr_handler = NULL; +} + +static bool handle_continuous_head_request(struct tegra_dma_channel *tdc, + struct tegra_dma_sg_req *last_sg_req, bool to_terminate) +{ + struct tegra_dma_sg_req *hsgreq = NULL; + + if (list_empty(&tdc->pending_sg_req)) { + dev_err(tdc2dev(tdc), "Dma is running without req\n"); + tegra_dma_stop(tdc); + return false; + } + + /* + * Check that head req on list should be in flight. + * If it is not in flight then abort transfer as + * looping of transfer can not continue. + */ + hsgreq = list_first_entry(&tdc->pending_sg_req, typeof(*hsgreq), node); + if (!hsgreq->configured) { + tegra_dma_stop(tdc); + dev_err(tdc2dev(tdc), "Error in dma transfer, aborting dma\n"); + tegra_dma_abort_all(tdc); + return false; + } + + /* Configure next request */ + if (!to_terminate) + tdc_configure_next_head_desc(tdc); + return true; +} + +static void handle_once_dma_done(struct tegra_dma_channel *tdc, + bool to_terminate) +{ + struct tegra_dma_sg_req *sgreq; + struct tegra_dma_desc *dma_desc; + + tdc->busy = false; + sgreq = list_first_entry(&tdc->pending_sg_req, typeof(*sgreq), node); + dma_desc = sgreq->dma_desc; + dma_desc->bytes_transferred += sgreq->req_len; + + list_del(&sgreq->node); + if (sgreq->last_sg) { + dma_desc->dma_status = DMA_SUCCESS; + dma_cookie_complete(&dma_desc->txd); + if (!dma_desc->cb_count) + list_add_tail(&dma_desc->cb_node, &tdc->cb_desc); + dma_desc->cb_count++; + list_add_tail(&dma_desc->node, &tdc->free_dma_desc); + } + list_add_tail(&sgreq->node, &tdc->free_sg_req); + + /* Do not start DMA if it is going to be terminate */ + if (to_terminate || list_empty(&tdc->pending_sg_req)) + return; + + tdc_start_head_req(tdc); + return; +} + +static void handle_cont_sngl_cycle_dma_done(struct tegra_dma_channel *tdc, + bool to_terminate) +{ + struct tegra_dma_sg_req *sgreq; + struct tegra_dma_desc *dma_desc; + bool st; + + sgreq = list_first_entry(&tdc->pending_sg_req, typeof(*sgreq), node); + dma_desc = sgreq->dma_desc; + dma_desc->bytes_transferred += sgreq->req_len; + + /* Callback need to be call */ + if (!dma_desc->cb_count) + list_add_tail(&dma_desc->cb_node, &tdc->cb_desc); + dma_desc->cb_count++; + + /* If not last req then put at end of pending list */ + if (!list_is_last(&sgreq->node, &tdc->pending_sg_req)) { + list_del(&sgreq->node); + list_add_tail(&sgreq->node, &tdc->pending_sg_req); + sgreq->configured = false; + st = handle_continuous_head_request(tdc, sgreq, to_terminate); + if (!st) + dma_desc->dma_status = DMA_ERROR; + } + return; +} + +static void tegra_dma_tasklet(unsigned long data) +{ + struct tegra_dma_channel *tdc = (struct tegra_dma_channel *)data; + dma_async_tx_callback callback = NULL; + void *callback_param = NULL; + struct tegra_dma_desc *dma_desc; + unsigned long flags; + int cb_count; + + spin_lock_irqsave(&tdc->lock, flags); + while (!list_empty(&tdc->cb_desc)) { + dma_desc = list_first_entry(&tdc->cb_desc, + typeof(*dma_desc), cb_node); + list_del(&dma_desc->cb_node); + callback = dma_desc->txd.callback; + callback_param = dma_desc->txd.callback_param; + cb_count = dma_desc->cb_count; + dma_desc->cb_count = 0; + spin_unlock_irqrestore(&tdc->lock, flags); + while (cb_count-- && callback) + callback(callback_param); + spin_lock_irqsave(&tdc->lock, flags); + } + spin_unlock_irqrestore(&tdc->lock, flags); +} + +static irqreturn_t tegra_dma_isr(int irq, void *dev_id) +{ + struct tegra_dma_channel *tdc = dev_id; + unsigned long status; + unsigned long flags; + + spin_lock_irqsave(&tdc->lock, flags); + + status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS); + if (status & TEGRA_APBDMA_STATUS_ISE_EOC) { + tdc_write(tdc, TEGRA_APBDMA_CHAN_STATUS, status); + tdc->isr_handler(tdc, false); + tasklet_schedule(&tdc->tasklet); + spin_unlock_irqrestore(&tdc->lock, flags); + return IRQ_HANDLED; + } + + spin_unlock_irqrestore(&tdc->lock, flags); + dev_info(tdc2dev(tdc), + "Interrupt already served status 0x%08lx\n", status); + return IRQ_NONE; +} + +static dma_cookie_t tegra_dma_tx_submit(struct dma_async_tx_descriptor *txd) +{ + struct tegra_dma_desc *dma_desc = txd_to_tegra_dma_desc(txd); + struct tegra_dma_channel *tdc = to_tegra_dma_chan(txd->chan); + unsigned long flags; + dma_cookie_t cookie; + + spin_lock_irqsave(&tdc->lock, flags); + dma_desc->dma_status = DMA_IN_PROGRESS; + cookie = dma_cookie_assign(&dma_desc->txd); + list_splice_tail_init(&dma_desc->tx_list, &tdc->pending_sg_req); + spin_unlock_irqrestore(&tdc->lock, flags); + return cookie; +} + +static void tegra_dma_issue_pending(struct dma_chan *dc) +{ + struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc); + unsigned long flags; + + spin_lock_irqsave(&tdc->lock, flags); + if (list_empty(&tdc->pending_sg_req)) { + dev_err(tdc2dev(tdc), "No DMA request\n"); + goto end; + } + if (!tdc->busy) { + tdc_start_head_req(tdc); + + /* Continuous single mode: Configure next req */ + if (tdc->cyclic) { + /* + * Wait for 1 burst time for configure DMA for + * next transfer. + */ + udelay(TEGRA_APBDMA_BURST_COMPLETE_TIME); + tdc_configure_next_head_desc(tdc); + } + } +end: + spin_unlock_irqrestore(&tdc->lock, flags); + return; +} + +static void tegra_dma_terminate_all(struct dma_chan *dc) +{ + struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc); + struct tegra_dma_sg_req *sgreq; + struct tegra_dma_desc *dma_desc; + unsigned long flags; + unsigned long status; + bool was_busy; + + spin_lock_irqsave(&tdc->lock, flags); + if (list_empty(&tdc->pending_sg_req)) { + spin_unlock_irqrestore(&tdc->lock, flags); + return; + } + + if (!tdc->busy) + goto skip_dma_stop; + + /* Pause DMA before checking the queue status */ + tegra_dma_global_pause(tdc, true); + + status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS); + if (status & TEGRA_APBDMA_STATUS_ISE_EOC) { + dev_dbg(tdc2dev(tdc), "%s():handling isr\n", __func__); + tdc->isr_handler(tdc, true); + status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS); + } + + was_busy = tdc->busy; + tegra_dma_stop(tdc); + + if (!list_empty(&tdc->pending_sg_req) && was_busy) { + sgreq = list_first_entry(&tdc->pending_sg_req, + typeof(*sgreq), node); + sgreq->dma_desc->bytes_transferred += + get_current_xferred_count(tdc, sgreq, status); + } + tegra_dma_global_resume(tdc); + +skip_dma_stop: + tegra_dma_abort_all(tdc); + + while (!list_empty(&tdc->cb_desc)) { + dma_desc = list_first_entry(&tdc->cb_desc, + typeof(*dma_desc), cb_node); + list_del(&dma_desc->cb_node); + dma_desc->cb_count = 0; + } + spin_unlock_irqrestore(&tdc->lock, flags); +} + +static enum dma_status tegra_dma_tx_status(struct dma_chan *dc, + dma_cookie_t cookie, struct dma_tx_state *txstate) +{ + struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc); + struct tegra_dma_desc *dma_desc; + struct tegra_dma_sg_req *sg_req; + enum dma_status ret; + unsigned long flags; + unsigned int residual; + + spin_lock_irqsave(&tdc->lock, flags); + + ret = dma_cookie_status(dc, cookie, txstate); + if (ret == DMA_SUCCESS) { + dma_set_residue(txstate, 0); + spin_unlock_irqrestore(&tdc->lock, flags); + return ret; + } + + /* Check on wait_ack desc status */ + list_for_each_entry(dma_desc, &tdc->free_dma_desc, node) { + if (dma_desc->txd.cookie == cookie) { + residual = dma_desc->bytes_requested - + (dma_desc->bytes_transferred % + dma_desc->bytes_requested); + dma_set_residue(txstate, residual); + ret = dma_desc->dma_status; + spin_unlock_irqrestore(&tdc->lock, flags); + return ret; + } + } + + /* Check in pending list */ + list_for_each_entry(sg_req, &tdc->pending_sg_req, node) { + dma_desc = sg_req->dma_desc; + if (dma_desc->txd.cookie == cookie) { + residual = dma_desc->bytes_requested - + (dma_desc->bytes_transferred % + dma_desc->bytes_requested); + dma_set_residue(txstate, residual); + ret = dma_desc->dma_status; + spin_unlock_irqrestore(&tdc->lock, flags); + return ret; + } + } + + dev_dbg(tdc2dev(tdc), "cookie %d does not found\n", cookie); + spin_unlock_irqrestore(&tdc->lock, flags); + return ret; +} + +static int tegra_dma_device_control(struct dma_chan *dc, enum dma_ctrl_cmd cmd, + unsigned long arg) +{ + switch (cmd) { + case DMA_SLAVE_CONFIG: + return tegra_dma_slave_config(dc, + (struct dma_slave_config *)arg); + + case DMA_TERMINATE_ALL: + tegra_dma_terminate_all(dc); + return 0; + + default: + break; + } + + return -ENXIO; +} + +static inline int get_bus_width(struct tegra_dma_channel *tdc, + enum dma_slave_buswidth slave_bw) +{ + switch (slave_bw) { + case DMA_SLAVE_BUSWIDTH_1_BYTE: + return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_8; + case DMA_SLAVE_BUSWIDTH_2_BYTES: + return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_16; + case DMA_SLAVE_BUSWIDTH_4_BYTES: + return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_32; + case DMA_SLAVE_BUSWIDTH_8_BYTES: + return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_64; + default: + dev_warn(tdc2dev(tdc), + "slave bw is not supported, using 32bits\n"); + return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_32; + } +} + +static inline int get_burst_size(struct tegra_dma_channel *tdc, + u32 burst_size, enum dma_slave_buswidth slave_bw, int len) +{ + int burst_byte; + int burst_ahb_width; + + /* + * burst_size from client is in terms of the bus_width. + * convert them into AHB memory width which is 4 byte. + */ + burst_byte = burst_size * slave_bw; + burst_ahb_width = burst_byte / 4; + + /* If burst size is 0 then calculate the burst size based on length */ + if (!burst_ahb_width) { + if (len & 0xF) + return TEGRA_APBDMA_AHBSEQ_BURST_1; + else if ((len >> 4) & 0x1) + return TEGRA_APBDMA_AHBSEQ_BURST_4; + else + return TEGRA_APBDMA_AHBSEQ_BURST_8; + } + if (burst_ahb_width < 4) + return TEGRA_APBDMA_AHBSEQ_BURST_1; + else if (burst_ahb_width < 8) + return TEGRA_APBDMA_AHBSEQ_BURST_4; + else + return TEGRA_APBDMA_AHBSEQ_BURST_8; +} + +static int get_transfer_param(struct tegra_dma_channel *tdc, + enum dma_transfer_direction direction, unsigned long *apb_addr, + unsigned long *apb_seq, unsigned long *csr, unsigned int *burst_size, + enum dma_slave_buswidth *slave_bw) +{ + + switch (direction) { + case DMA_MEM_TO_DEV: + *apb_addr = tdc->dma_sconfig.dst_addr; + *apb_seq = get_bus_width(tdc, tdc->dma_sconfig.dst_addr_width); + *burst_size = tdc->dma_sconfig.dst_maxburst; + *slave_bw = tdc->dma_sconfig.dst_addr_width; + *csr = TEGRA_APBDMA_CSR_DIR; + return 0; + + case DMA_DEV_TO_MEM: + *apb_addr = tdc->dma_sconfig.src_addr; + *apb_seq = get_bus_width(tdc, tdc->dma_sconfig.src_addr_width); + *burst_size = tdc->dma_sconfig.src_maxburst; + *slave_bw = tdc->dma_sconfig.src_addr_width; + *csr = 0; + return 0; + + default: + dev_err(tdc2dev(tdc), "Dma direction is not supported\n"); + return -EINVAL; + } + return -EINVAL; +} + +static struct dma_async_tx_descriptor *tegra_dma_prep_slave_sg( + struct dma_chan *dc, struct scatterlist *sgl, unsigned int sg_len, + enum dma_transfer_direction direction, unsigned long flags, + void *context) +{ + struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc); + struct tegra_dma_desc *dma_desc; + unsigned int i; + struct scatterlist *sg; + unsigned long csr, ahb_seq, apb_ptr, apb_seq; + struct list_head req_list; + struct tegra_dma_sg_req *sg_req = NULL; + u32 burst_size; + enum dma_slave_buswidth slave_bw; + int ret; + + if (!tdc->config_init) { + dev_err(tdc2dev(tdc), "dma channel is not configured\n"); + return NULL; + } + if (sg_len < 1) { + dev_err(tdc2dev(tdc), "Invalid segment length %d\n", sg_len); + return NULL; + } + + ret = get_transfer_param(tdc, direction, &apb_ptr, &apb_seq, &csr, + &burst_size, &slave_bw); + if (ret < 0) + return NULL; + + INIT_LIST_HEAD(&req_list); + + ahb_seq = TEGRA_APBDMA_AHBSEQ_INTR_ENB; + ahb_seq |= TEGRA_APBDMA_AHBSEQ_WRAP_NONE << + TEGRA_APBDMA_AHBSEQ_WRAP_SHIFT; + ahb_seq |= TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_32; + + csr |= TEGRA_APBDMA_CSR_ONCE | TEGRA_APBDMA_CSR_FLOW; + csr |= tdc->dma_sconfig.slave_id << TEGRA_APBDMA_CSR_REQ_SEL_SHIFT; + if (flags & DMA_PREP_INTERRUPT) + csr |= TEGRA_APBDMA_CSR_IE_EOC; + + apb_seq |= TEGRA_APBDMA_APBSEQ_WRAP_WORD_1; + + dma_desc = tegra_dma_desc_get(tdc); + if (!dma_desc) { + dev_err(tdc2dev(tdc), "Dma descriptors not available\n"); + return NULL; + } + INIT_LIST_HEAD(&dma_desc->tx_list); + INIT_LIST_HEAD(&dma_desc->cb_node); + dma_desc->cb_count = 0; + dma_desc->bytes_requested = 0; + dma_desc->bytes_transferred = 0; + dma_desc->dma_status = DMA_IN_PROGRESS; + + /* Make transfer requests */ + for_each_sg(sgl, sg, sg_len, i) { + u32 len, mem; + + mem = sg_dma_address(sg); + len = sg_dma_len(sg); + + if ((len & 3) || (mem & 3) || + (len > tdc->tdma->chip_data->max_dma_count)) { + dev_err(tdc2dev(tdc), + "Dma length/memory address is not supported\n"); + tegra_dma_desc_put(tdc, dma_desc); + return NULL; + } + + sg_req = tegra_dma_sg_req_get(tdc); + if (!sg_req) { + dev_err(tdc2dev(tdc), "Dma sg-req not available\n"); + tegra_dma_desc_put(tdc, dma_desc); + return NULL; + } + + ahb_seq |= get_burst_size(tdc, burst_size, slave_bw, len); + dma_desc->bytes_requested += len; + + sg_req->ch_regs.apb_ptr = apb_ptr; + sg_req->ch_regs.ahb_ptr = mem; + sg_req->ch_regs.csr = csr | ((len - 4) & 0xFFFC); + sg_req->ch_regs.apb_seq = apb_seq; + sg_req->ch_regs.ahb_seq = ahb_seq; + sg_req->configured = false; + sg_req->last_sg = false; + sg_req->dma_desc = dma_desc; + sg_req->req_len = len; + + list_add_tail(&sg_req->node, &dma_desc->tx_list); + } + sg_req->last_sg = true; + if (flags & DMA_CTRL_ACK) + dma_desc->txd.flags = DMA_CTRL_ACK; + + /* + * Make sure that mode should not be conflicting with currently + * configured mode. + */ + if (!tdc->isr_handler) { + tdc->isr_handler = handle_once_dma_done; + tdc->cyclic = false; + } else { + if (tdc->cyclic) { + dev_err(tdc2dev(tdc), "DMA configured in cyclic mode\n"); + tegra_dma_desc_put(tdc, dma_desc); + return NULL; + } + } + + return &dma_desc->txd; +} + +struct dma_async_tx_descriptor *tegra_dma_prep_dma_cyclic( + struct dma_chan *dc, dma_addr_t buf_addr, size_t buf_len, + size_t period_len, enum dma_transfer_direction direction, + void *context) +{ + struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc); + struct tegra_dma_desc *dma_desc = NULL; + struct tegra_dma_sg_req *sg_req = NULL; + unsigned long csr, ahb_seq, apb_ptr, apb_seq; + int len; + size_t remain_len; + dma_addr_t mem = buf_addr; + u32 burst_size; + enum dma_slave_buswidth slave_bw; + int ret; + + if (!buf_len || !period_len) { + dev_err(tdc2dev(tdc), "Invalid buffer/period len\n"); + return NULL; + } + + if (!tdc->config_init) { + dev_err(tdc2dev(tdc), "DMA slave is not configured\n"); + return NULL; + } + + /* + * We allow to take more number of requests till DMA is + * not started. The driver will loop over all requests. + * Once DMA is started then new requests can be queued only after + * terminating the DMA. + */ + if (tdc->busy) { + dev_err(tdc2dev(tdc), "Request not allowed when dma running\n"); + return NULL; + } + + /* + * We only support cycle transfer when buf_len is multiple of + * period_len. + */ + if (buf_len % period_len) { + dev_err(tdc2dev(tdc), "buf_len is not multiple of period_len\n"); + return NULL; + } + + len = period_len; + if ((len & 3) || (buf_addr & 3) || + (len > tdc->tdma->chip_data->max_dma_count)) { + dev_err(tdc2dev(tdc), "Req len/mem address is not correct\n"); + return NULL; + } + + ret = get_transfer_param(tdc, direction, &apb_ptr, &apb_seq, &csr, + &burst_size, &slave_bw); + if (ret < 0) + return NULL; + + + ahb_seq = TEGRA_APBDMA_AHBSEQ_INTR_ENB; + ahb_seq |= TEGRA_APBDMA_AHBSEQ_WRAP_NONE << + TEGRA_APBDMA_AHBSEQ_WRAP_SHIFT; + ahb_seq |= TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_32; + + csr |= TEGRA_APBDMA_CSR_FLOW | TEGRA_APBDMA_CSR_IE_EOC; + csr |= tdc->dma_sconfig.slave_id << TEGRA_APBDMA_CSR_REQ_SEL_SHIFT; + + apb_seq |= TEGRA_APBDMA_APBSEQ_WRAP_WORD_1; + + dma_desc = tegra_dma_desc_get(tdc); + if (!dma_desc) { + dev_err(tdc2dev(tdc), "not enough descriptors available\n"); + return NULL; + } + + INIT_LIST_HEAD(&dma_desc->tx_list); + INIT_LIST_HEAD(&dma_desc->cb_node); + dma_desc->cb_count = 0; + + dma_desc->bytes_transferred = 0; + dma_desc->bytes_requested = buf_len; + remain_len = buf_len; + + /* Split transfer equal to period size */ + while (remain_len) { + sg_req = tegra_dma_sg_req_get(tdc); + if (!sg_req) { + dev_err(tdc2dev(tdc), "Dma sg-req not available\n"); + tegra_dma_desc_put(tdc, dma_desc); + return NULL; + } + + ahb_seq |= get_burst_size(tdc, burst_size, slave_bw, len); + sg_req->ch_regs.apb_ptr = apb_ptr; + sg_req->ch_regs.ahb_ptr = mem; + sg_req->ch_regs.csr = csr | ((len - 4) & 0xFFFC); + sg_req->ch_regs.apb_seq = apb_seq; + sg_req->ch_regs.ahb_seq = ahb_seq; + sg_req->configured = false; + sg_req->half_done = false; + sg_req->last_sg = false; + sg_req->dma_desc = dma_desc; + sg_req->req_len = len; + + list_add_tail(&sg_req->node, &dma_desc->tx_list); + remain_len -= len; + mem += len; + } + sg_req->last_sg = true; + dma_desc->txd.flags = 0; + + /* + * Make sure that mode should not be conflicting with currently + * configured mode. + */ + if (!tdc->isr_handler) { + tdc->isr_handler = handle_cont_sngl_cycle_dma_done; + tdc->cyclic = true; + } else { + if (!tdc->cyclic) { + dev_err(tdc2dev(tdc), "DMA configuration conflict\n"); + tegra_dma_desc_put(tdc, dma_desc); + return NULL; + } + } + + return &dma_desc->txd; +} + +static int tegra_dma_alloc_chan_resources(struct dma_chan *dc) +{ + struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc); + + dma_cookie_init(&tdc->dma_chan); + tdc->config_init = false; + return 0; +} + +static void tegra_dma_free_chan_resources(struct dma_chan *dc) +{ + struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc); + + struct tegra_dma_desc *dma_desc; + struct tegra_dma_sg_req *sg_req; + struct list_head dma_desc_list; + struct list_head sg_req_list; + unsigned long flags; + + INIT_LIST_HEAD(&dma_desc_list); + INIT_LIST_HEAD(&sg_req_list); + + dev_dbg(tdc2dev(tdc), "Freeing channel %d\n", tdc->id); + + if (tdc->busy) + tegra_dma_terminate_all(dc); + + spin_lock_irqsave(&tdc->lock, flags); + list_splice_init(&tdc->pending_sg_req, &sg_req_list); + list_splice_init(&tdc->free_sg_req, &sg_req_list); + list_splice_init(&tdc->free_dma_desc, &dma_desc_list); + INIT_LIST_HEAD(&tdc->cb_desc); + tdc->config_init = false; + spin_unlock_irqrestore(&tdc->lock, flags); + + while (!list_empty(&dma_desc_list)) { + dma_desc = list_first_entry(&dma_desc_list, + typeof(*dma_desc), node); + list_del(&dma_desc->node); + kfree(dma_desc); + } + + while (!list_empty(&sg_req_list)) { + sg_req = list_first_entry(&sg_req_list, typeof(*sg_req), node); + list_del(&sg_req->node); + kfree(sg_req); + } +} + +/* Tegra20 specific DMA controller information */ +static struct tegra_dma_chip_data tegra20_dma_chip_data = { + .nr_channels = 16, + .max_dma_count = 1024UL * 64, +}; + +#if defined(CONFIG_OF) +/* Tegra30 specific DMA controller information */ +static struct tegra_dma_chip_data tegra30_dma_chip_data = { + .nr_channels = 32, + .max_dma_count = 1024UL * 64, +}; + +static const struct of_device_id tegra_dma_of_match[] __devinitconst = { + { + .compatible = "nvidia,tegra30-apbdma", + .data = &tegra30_dma_chip_data, + }, { + .compatible = "nvidia,tegra20-apbdma", + .data = &tegra20_dma_chip_data, + }, { + }, +}; +MODULE_DEVICE_TABLE(of, tegra_dma_of_match); +#endif + +static int __devinit tegra_dma_probe(struct platform_device *pdev) +{ + struct resource *res; + struct tegra_dma *tdma; + int ret; + int i; + struct tegra_dma_chip_data *cdata = NULL; + + if (pdev->dev.of_node) { + const struct of_device_id *match; + match = of_match_device(of_match_ptr(tegra_dma_of_match), + &pdev->dev); + if (!match) { + dev_err(&pdev->dev, "Error: No device match found\n"); + return -ENODEV; + } + cdata = match->data; + } else { + /* If no device tree then fallback to tegra20 */ + cdata = &tegra20_dma_chip_data; + } + + tdma = devm_kzalloc(&pdev->dev, sizeof(*tdma) + cdata->nr_channels * + sizeof(struct tegra_dma_channel), GFP_KERNEL); + if (!tdma) { + dev_err(&pdev->dev, "Error: memory allocation failed\n"); + return -ENOMEM; + } + + tdma->dev = &pdev->dev; + tdma->chip_data = cdata; + platform_set_drvdata(pdev, tdma); + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) { + dev_err(&pdev->dev, "No mem resource for DMA\n"); + return -EINVAL; + } + + tdma->base_addr = devm_request_and_ioremap(&pdev->dev, res); + if (!tdma->base_addr) { + dev_err(&pdev->dev, + "Cannot request memregion/iomap dma address\n"); + return -EADDRNOTAVAIL; + } + + tdma->dma_clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(tdma->dma_clk)) { + dev_err(&pdev->dev, "Error: Missing controller clock\n"); + return PTR_ERR(tdma->dma_clk); + } + + spin_lock_init(&tdma->global_lock); + + pm_runtime_enable(&pdev->dev); + if (!pm_runtime_enabled(&pdev->dev)) { + ret = tegra_dma_runtime_resume(&pdev->dev); + if (ret) { + dev_err(&pdev->dev, "dma_runtime_resume failed %d\n", + ret); + goto err_pm_disable; + } + } + + /* Reset DMA controller */ + tegra_periph_reset_assert(tdma->dma_clk); + udelay(2); + tegra_periph_reset_deassert(tdma->dma_clk); + + /* Enable global DMA registers */ + tdma_write(tdma, TEGRA_APBDMA_GENERAL, TEGRA_APBDMA_GENERAL_ENABLE); + tdma_write(tdma, TEGRA_APBDMA_CONTROL, 0); + tdma_write(tdma, TEGRA_APBDMA_IRQ_MASK_SET, 0xFFFFFFFFul); + + INIT_LIST_HEAD(&tdma->dma_dev.channels); + for (i = 0; i < cdata->nr_channels; i++) { + struct tegra_dma_channel *tdc = &tdma->channels[i]; + char irq_name[30]; + + tdc->chan_base_offset = TEGRA_APBDMA_CHANNEL_BASE_ADD_OFFSET + + i * TEGRA_APBDMA_CHANNEL_REGISTER_SIZE; + + res = platform_get_resource(pdev, IORESOURCE_IRQ, i); + if (!res) { + ret = -EINVAL; + dev_err(&pdev->dev, "No irq resource for chan %d\n", i); + goto err_irq; + } + tdc->irq = res->start; + snprintf(irq_name, sizeof(irq_name), "apbdma.%d", i); + ret = devm_request_irq(&pdev->dev, tdc->irq, + tegra_dma_isr, 0, irq_name, tdc); + if (ret) { + dev_err(&pdev->dev, + "request_irq failed with err %d channel %d\n", + i, ret); + goto err_irq; + } + + tdc->dma_chan.device = &tdma->dma_dev; + dma_cookie_init(&tdc->dma_chan); + list_add_tail(&tdc->dma_chan.device_node, + &tdma->dma_dev.channels); + tdc->tdma = tdma; + tdc->id = i; + + tasklet_init(&tdc->tasklet, tegra_dma_tasklet, + (unsigned long)tdc); + spin_lock_init(&tdc->lock); + + INIT_LIST_HEAD(&tdc->pending_sg_req); + INIT_LIST_HEAD(&tdc->free_sg_req); + INIT_LIST_HEAD(&tdc->free_dma_desc); + INIT_LIST_HEAD(&tdc->cb_desc); + } + + dma_cap_set(DMA_SLAVE, tdma->dma_dev.cap_mask); + dma_cap_set(DMA_PRIVATE, tdma->dma_dev.cap_mask); + dma_cap_set(DMA_CYCLIC, tdma->dma_dev.cap_mask); + + tdma->dma_dev.dev = &pdev->dev; + tdma->dma_dev.device_alloc_chan_resources = + tegra_dma_alloc_chan_resources; + tdma->dma_dev.device_free_chan_resources = + tegra_dma_free_chan_resources; + tdma->dma_dev.device_prep_slave_sg = tegra_dma_prep_slave_sg; + tdma->dma_dev.device_prep_dma_cyclic = tegra_dma_prep_dma_cyclic; + tdma->dma_dev.device_control = tegra_dma_device_control; + tdma->dma_dev.device_tx_status = tegra_dma_tx_status; + tdma->dma_dev.device_issue_pending = tegra_dma_issue_pending; + + ret = dma_async_device_register(&tdma->dma_dev); + if (ret < 0) { + dev_err(&pdev->dev, + "Tegra20 APB DMA driver registration failed %d\n", ret); + goto err_irq; + } + + dev_info(&pdev->dev, "Tegra20 APB DMA driver register %d channels\n", + cdata->nr_channels); + return 0; + +err_irq: + while (--i >= 0) { + struct tegra_dma_channel *tdc = &tdma->channels[i]; + tasklet_kill(&tdc->tasklet); + } + +err_pm_disable: + pm_runtime_disable(&pdev->dev); + if (!pm_runtime_status_suspended(&pdev->dev)) + tegra_dma_runtime_suspend(&pdev->dev); + return ret; +} + +static int __devexit tegra_dma_remove(struct platform_device *pdev) +{ + struct tegra_dma *tdma = platform_get_drvdata(pdev); + int i; + struct tegra_dma_channel *tdc; + + dma_async_device_unregister(&tdma->dma_dev); + + for (i = 0; i < tdma->chip_data->nr_channels; ++i) { + tdc = &tdma->channels[i]; + tasklet_kill(&tdc->tasklet); + } + + pm_runtime_disable(&pdev->dev); + if (!pm_runtime_status_suspended(&pdev->dev)) + tegra_dma_runtime_suspend(&pdev->dev); + + return 0; +} + +static int tegra_dma_runtime_suspend(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct tegra_dma *tdma = platform_get_drvdata(pdev); + + clk_disable_unprepare(tdma->dma_clk); + return 0; +} + +static int tegra_dma_runtime_resume(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct tegra_dma *tdma = platform_get_drvdata(pdev); + int ret; + + ret = clk_prepare_enable(tdma->dma_clk); + if (ret < 0) { + dev_err(dev, "clk_enable failed: %d\n", ret); + return ret; + } + return 0; +} + +static const struct dev_pm_ops tegra_dma_dev_pm_ops __devinitconst = { +#ifdef CONFIG_PM_RUNTIME + .runtime_suspend = tegra_dma_runtime_suspend, + .runtime_resume = tegra_dma_runtime_resume, +#endif +}; + +static struct platform_driver tegra_dmac_driver = { + .driver = { + .name = "tegra-apbdma", + .owner = THIS_MODULE, + .pm = &tegra_dma_dev_pm_ops, + .of_match_table = of_match_ptr(tegra_dma_of_match), + }, + .probe = tegra_dma_probe, + .remove = __devexit_p(tegra_dma_remove), +}; + +module_platform_driver(tegra_dmac_driver); + +MODULE_ALIAS("platform:tegra20-apbdma"); +MODULE_DESCRIPTION("NVIDIA Tegra APB DMA Controller driver"); +MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>"); +MODULE_LICENSE("GPL v2"); |
