diff options
Diffstat (limited to 'drivers/spi/spi-nuc900.c')
-rw-r--r-- | drivers/spi/spi-nuc900.c | 426 |
1 files changed, 0 insertions, 426 deletions
diff --git a/drivers/spi/spi-nuc900.c b/drivers/spi/spi-nuc900.c deleted file mode 100644 index 61400358f4be..000000000000 --- a/drivers/spi/spi-nuc900.c +++ /dev/null @@ -1,426 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-only -/* - * Copyright (c) 2009 Nuvoton technology. - * Wan ZongShun <mcuos.com@gmail.com> - */ - -#include <linux/module.h> -#include <linux/spinlock.h> -#include <linux/interrupt.h> -#include <linux/delay.h> -#include <linux/errno.h> -#include <linux/err.h> -#include <linux/clk.h> -#include <linux/device.h> -#include <linux/platform_device.h> -#include <linux/gpio.h> -#include <linux/io.h> -#include <linux/slab.h> - -#include <linux/spi/spi.h> -#include <linux/spi/spi_bitbang.h> - -#include <linux/platform_data/spi-nuc900.h> - -/* usi registers offset */ -#define USI_CNT 0x00 -#define USI_DIV 0x04 -#define USI_SSR 0x08 -#define USI_RX0 0x10 -#define USI_TX0 0x10 - -/* usi register bit */ -#define ENINT (0x01 << 17) -#define ENFLG (0x01 << 16) -#define SLEEP (0x0f << 12) -#define TXNUM (0x03 << 8) -#define TXBITLEN (0x1f << 3) -#define TXNEG (0x01 << 2) -#define RXNEG (0x01 << 1) -#define LSB (0x01 << 10) -#define SELECTLEV (0x01 << 2) -#define SELECTPOL (0x01 << 31) -#define SELECTSLAVE 0x01 -#define GOBUSY 0x01 - -struct nuc900_spi { - struct spi_bitbang bitbang; - struct completion done; - void __iomem *regs; - int irq; - int len; - int count; - const unsigned char *tx; - unsigned char *rx; - struct clk *clk; - struct spi_master *master; - struct nuc900_spi_info *pdata; - spinlock_t lock; -}; - -static inline struct nuc900_spi *to_hw(struct spi_device *sdev) -{ - return spi_master_get_devdata(sdev->master); -} - -static void nuc900_slave_select(struct spi_device *spi, unsigned int ssr) -{ - struct nuc900_spi *hw = to_hw(spi); - unsigned int val; - unsigned int cs = spi->mode & SPI_CS_HIGH ? 1 : 0; - unsigned int cpol = spi->mode & SPI_CPOL ? 1 : 0; - unsigned long flags; - - spin_lock_irqsave(&hw->lock, flags); - - val = __raw_readl(hw->regs + USI_SSR); - - if (!cs) - val &= ~SELECTLEV; - else - val |= SELECTLEV; - - if (!ssr) - val &= ~SELECTSLAVE; - else - val |= SELECTSLAVE; - - __raw_writel(val, hw->regs + USI_SSR); - - val = __raw_readl(hw->regs + USI_CNT); - - if (!cpol) - val &= ~SELECTPOL; - else - val |= SELECTPOL; - - __raw_writel(val, hw->regs + USI_CNT); - - spin_unlock_irqrestore(&hw->lock, flags); -} - -static void nuc900_spi_chipsel(struct spi_device *spi, int value) -{ - switch (value) { - case BITBANG_CS_INACTIVE: - nuc900_slave_select(spi, 0); - break; - - case BITBANG_CS_ACTIVE: - nuc900_slave_select(spi, 1); - break; - } -} - -static void nuc900_spi_setup_txnum(struct nuc900_spi *hw, unsigned int txnum) -{ - unsigned int val; - unsigned long flags; - - spin_lock_irqsave(&hw->lock, flags); - - val = __raw_readl(hw->regs + USI_CNT) & ~TXNUM; - - if (txnum) - val |= txnum << 0x08; - - __raw_writel(val, hw->regs + USI_CNT); - - spin_unlock_irqrestore(&hw->lock, flags); - -} - -static void nuc900_spi_setup_txbitlen(struct nuc900_spi *hw, - unsigned int txbitlen) -{ - unsigned int val; - unsigned long flags; - - spin_lock_irqsave(&hw->lock, flags); - - val = __raw_readl(hw->regs + USI_CNT) & ~TXBITLEN; - - val |= (txbitlen << 0x03); - - __raw_writel(val, hw->regs + USI_CNT); - - spin_unlock_irqrestore(&hw->lock, flags); -} - -static void nuc900_spi_gobusy(struct nuc900_spi *hw) -{ - unsigned int val; - unsigned long flags; - - spin_lock_irqsave(&hw->lock, flags); - - val = __raw_readl(hw->regs + USI_CNT); - - val |= GOBUSY; - - __raw_writel(val, hw->regs + USI_CNT); - - spin_unlock_irqrestore(&hw->lock, flags); -} - -static inline unsigned int hw_txbyte(struct nuc900_spi *hw, int count) -{ - return hw->tx ? hw->tx[count] : 0; -} - -static int nuc900_spi_txrx(struct spi_device *spi, struct spi_transfer *t) -{ - struct nuc900_spi *hw = to_hw(spi); - - hw->tx = t->tx_buf; - hw->rx = t->rx_buf; - hw->len = t->len; - hw->count = 0; - - __raw_writel(hw_txbyte(hw, 0x0), hw->regs + USI_TX0); - - nuc900_spi_gobusy(hw); - - wait_for_completion(&hw->done); - - return hw->count; -} - -static irqreturn_t nuc900_spi_irq(int irq, void *dev) -{ - struct nuc900_spi *hw = dev; - unsigned int status; - unsigned int count = hw->count; - - status = __raw_readl(hw->regs + USI_CNT); - __raw_writel(status, hw->regs + USI_CNT); - - if (status & ENFLG) { - hw->count++; - - if (hw->rx) - hw->rx[count] = __raw_readl(hw->regs + USI_RX0); - count++; - - if (count < hw->len) { - __raw_writel(hw_txbyte(hw, count), hw->regs + USI_TX0); - nuc900_spi_gobusy(hw); - } else { - complete(&hw->done); - } - - return IRQ_HANDLED; - } - - complete(&hw->done); - return IRQ_HANDLED; -} - -static void nuc900_tx_edge(struct nuc900_spi *hw, unsigned int edge) -{ - unsigned int val; - unsigned long flags; - - spin_lock_irqsave(&hw->lock, flags); - - val = __raw_readl(hw->regs + USI_CNT); - - if (edge) - val |= TXNEG; - else - val &= ~TXNEG; - __raw_writel(val, hw->regs + USI_CNT); - - spin_unlock_irqrestore(&hw->lock, flags); -} - -static void nuc900_rx_edge(struct nuc900_spi *hw, unsigned int edge) -{ - unsigned int val; - unsigned long flags; - - spin_lock_irqsave(&hw->lock, flags); - - val = __raw_readl(hw->regs + USI_CNT); - - if (edge) - val |= RXNEG; - else - val &= ~RXNEG; - __raw_writel(val, hw->regs + USI_CNT); - - spin_unlock_irqrestore(&hw->lock, flags); -} - -static void nuc900_send_first(struct nuc900_spi *hw, unsigned int lsb) -{ - unsigned int val; - unsigned long flags; - - spin_lock_irqsave(&hw->lock, flags); - - val = __raw_readl(hw->regs + USI_CNT); - - if (lsb) - val |= LSB; - else - val &= ~LSB; - __raw_writel(val, hw->regs + USI_CNT); - - spin_unlock_irqrestore(&hw->lock, flags); -} - -static void nuc900_set_sleep(struct nuc900_spi *hw, unsigned int sleep) -{ - unsigned int val; - unsigned long flags; - - spin_lock_irqsave(&hw->lock, flags); - - val = __raw_readl(hw->regs + USI_CNT) & ~SLEEP; - - if (sleep) - val |= (sleep << 12); - - __raw_writel(val, hw->regs + USI_CNT); - - spin_unlock_irqrestore(&hw->lock, flags); -} - -static void nuc900_enable_int(struct nuc900_spi *hw) -{ - unsigned int val; - unsigned long flags; - - spin_lock_irqsave(&hw->lock, flags); - - val = __raw_readl(hw->regs + USI_CNT); - - val |= ENINT; - - __raw_writel(val, hw->regs + USI_CNT); - - spin_unlock_irqrestore(&hw->lock, flags); -} - -static void nuc900_set_divider(struct nuc900_spi *hw) -{ - __raw_writel(hw->pdata->divider, hw->regs + USI_DIV); -} - -static void nuc900_init_spi(struct nuc900_spi *hw) -{ - clk_enable(hw->clk); - spin_lock_init(&hw->lock); - - nuc900_tx_edge(hw, hw->pdata->txneg); - nuc900_rx_edge(hw, hw->pdata->rxneg); - nuc900_send_first(hw, hw->pdata->lsb); - nuc900_set_sleep(hw, hw->pdata->sleep); - nuc900_spi_setup_txbitlen(hw, hw->pdata->txbitlen); - nuc900_spi_setup_txnum(hw, hw->pdata->txnum); - nuc900_set_divider(hw); - nuc900_enable_int(hw); -} - -static int nuc900_spi_probe(struct platform_device *pdev) -{ - struct nuc900_spi *hw; - struct spi_master *master; - int err = 0; - - master = spi_alloc_master(&pdev->dev, sizeof(struct nuc900_spi)); - if (master == NULL) { - dev_err(&pdev->dev, "No memory for spi_master\n"); - return -ENOMEM; - } - - hw = spi_master_get_devdata(master); - hw->master = master; - hw->pdata = dev_get_platdata(&pdev->dev); - - if (hw->pdata == NULL) { - dev_err(&pdev->dev, "No platform data supplied\n"); - err = -ENOENT; - goto err_pdata; - } - - platform_set_drvdata(pdev, hw); - init_completion(&hw->done); - - master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH; - if (hw->pdata->lsb) - master->mode_bits |= SPI_LSB_FIRST; - master->num_chipselect = hw->pdata->num_cs; - master->bus_num = hw->pdata->bus_num; - hw->bitbang.master = hw->master; - hw->bitbang.chipselect = nuc900_spi_chipsel; - hw->bitbang.txrx_bufs = nuc900_spi_txrx; - - hw->regs = devm_platform_ioremap_resource(pdev, 0); - if (IS_ERR(hw->regs)) { - err = PTR_ERR(hw->regs); - goto err_pdata; - } - - hw->irq = platform_get_irq(pdev, 0); - if (hw->irq < 0) { - err = -ENOENT; - goto err_pdata; - } - - err = devm_request_irq(&pdev->dev, hw->irq, nuc900_spi_irq, 0, - pdev->name, hw); - if (err) { - dev_err(&pdev->dev, "Cannot claim IRQ\n"); - goto err_pdata; - } - - hw->clk = devm_clk_get(&pdev->dev, "spi"); - if (IS_ERR(hw->clk)) { - dev_err(&pdev->dev, "No clock for device\n"); - err = PTR_ERR(hw->clk); - goto err_pdata; - } - - mfp_set_groupg(&pdev->dev, NULL); - nuc900_init_spi(hw); - - err = spi_bitbang_start(&hw->bitbang); - if (err) { - dev_err(&pdev->dev, "Failed to register SPI master\n"); - goto err_register; - } - - return 0; - -err_register: - clk_disable(hw->clk); -err_pdata: - spi_master_put(hw->master); - return err; -} - -static int nuc900_spi_remove(struct platform_device *dev) -{ - struct nuc900_spi *hw = platform_get_drvdata(dev); - - spi_bitbang_stop(&hw->bitbang); - clk_disable(hw->clk); - spi_master_put(hw->master); - return 0; -} - -static struct platform_driver nuc900_spi_driver = { - .probe = nuc900_spi_probe, - .remove = nuc900_spi_remove, - .driver = { - .name = "nuc900-spi", - }, -}; -module_platform_driver(nuc900_spi_driver); - -MODULE_AUTHOR("Wan ZongShun <mcuos.com@gmail.com>"); -MODULE_DESCRIPTION("nuc900 spi driver!"); -MODULE_LICENSE("GPL"); -MODULE_ALIAS("platform:nuc900-spi"); |