--- /dev/null
+/*
+ * TI QSPI driver
+ *
+ * Copyright (C) 2013 Texas Instruments Incorporated - http://www.ti.com
+ * Author: Sourav Poddar <sourav.poddar@ti.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GPLv2.
+ *
+ * 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.
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/delay.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmaengine.h>
+#include <linux/omap-dma.h>
+#include <linux/platform_device.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/pm_runtime.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/pinctrl/consumer.h>
+
+#include <linux/spi/spi.h>
+
+struct ti_qspi_regs {
+ u32 clkctrl;
+};
+
+struct ti_qspi {
+ struct completion transfer_complete;
+
+ /* IRQ synchronization */
+ spinlock_t lock;
+
+ /* list synchronization */
+ struct mutex list_lock;
+
+ struct spi_master *master;
+ void __iomem *base;
+ struct clk *fclk;
+ struct device *dev;
+
+ struct ti_qspi_regs ctx_reg;
+
+ u32 spi_max_frequency;
+ u32 cmd;
+ u32 dc;
+ u32 stat;
+};
+
+#define QSPI_PID (0x0)
+#define QSPI_SYSCONFIG (0x10)
+#define QSPI_INTR_STATUS_RAW_SET (0x20)
+#define QSPI_INTR_STATUS_ENABLED_CLEAR (0x24)
+#define QSPI_INTR_ENABLE_SET_REG (0x28)
+#define QSPI_INTR_ENABLE_CLEAR_REG (0x2c)
+#define QSPI_SPI_CLOCK_CNTRL_REG (0x40)
+#define QSPI_SPI_DC_REG (0x44)
+#define QSPI_SPI_CMD_REG (0x48)
+#define QSPI_SPI_STATUS_REG (0x4c)
+#define QSPI_SPI_DATA_REG (0x50)
+#define QSPI_SPI_SETUP0_REG (0x54)
+#define QSPI_SPI_SWITCH_REG (0x64)
+#define QSPI_SPI_SETUP1_REG (0x58)
+#define QSPI_SPI_SETUP2_REG (0x5c)
+#define QSPI_SPI_SETUP3_REG (0x60)
+#define QSPI_SPI_DATA_REG_1 (0x68)
+#define QSPI_SPI_DATA_REG_2 (0x6c)
+#define QSPI_SPI_DATA_REG_3 (0x70)
+
+#define QSPI_COMPLETION_TIMEOUT msecs_to_jiffies(2000)
+
+#define QSPI_FCLK 192000000
+
+/* Clock Control */
+#define QSPI_CLK_EN (1 << 31)
+#define QSPI_CLK_DIV_MAX 0xffff
+
+/* Command */
+#define QSPI_EN_CS(n) (n << 28)
+#define QSPI_WLEN(n) ((n - 1) << 19)
+#define QSPI_3_PIN (1 << 18)
+#define QSPI_RD_SNGL (1 << 16)
+#define QSPI_WR_SNGL (2 << 16)
+#define QSPI_RD_DUAL (3 << 16)
+#define QSPI_RD_QUAD (7 << 16)
+#define QSPI_INVAL (4 << 16)
+#define QSPI_WC_CMD_INT_EN (1 << 14)
+#define QSPI_FLEN(n) ((n - 1) << 0)
+
+/* STATUS REGISTER */
+#define WC 0x02
+
+/* INTERRUPT REGISTER */
+#define QSPI_WC_INT_EN (1 << 1)
+#define QSPI_WC_INT_DISABLE (1 << 1)
+
+/* Device Control */
+#define QSPI_DD(m, n) (m << (3 + n * 8))
+#define QSPI_CKPHA(n) (1 << (2 + n * 8))
+#define QSPI_CSPOL(n) (1 << (1 + n * 8))
+#define QSPI_CKPOL(n) (1 << (n * 8))
+
+#define QSPI_FRAME 4096
+
+#define QSPI_AUTOSUSPEND_TIMEOUT 2000
+
+static inline unsigned long ti_qspi_read(struct ti_qspi *qspi,
+ unsigned long reg)
+{
+ return readl(qspi->base + reg);
+}
+
+static inline void ti_qspi_write(struct ti_qspi *qspi,
+ unsigned long val, unsigned long reg)
+{
+ writel(val, qspi->base + reg);
+}
+
+static int ti_qspi_setup(struct spi_device *spi)
+{
+ struct ti_qspi *qspi = spi_master_get_devdata(spi->master);
+ struct ti_qspi_regs *ctx_reg = &qspi->ctx_reg;
+ int clk_div = 0, ret;
+ u32 clk_ctrl_reg, clk_rate, clk_mask;
+
+ if (spi->master->busy) {
+ dev_dbg(qspi->dev, "master busy doing other trasnfers\n");
+ return -EBUSY;
+ }
+
+ if (!qspi->spi_max_frequency) {
+ dev_err(qspi->dev, "spi max frequency not defined\n");
+ return -EINVAL;
+ }
+
+ clk_rate = clk_get_rate(qspi->fclk);
+
+ clk_div = DIV_ROUND_UP(clk_rate, qspi->spi_max_frequency) - 1;
+
+ if (clk_div < 0) {
+ dev_dbg(qspi->dev, "clock divider < 0, using /1 divider\n");
+ return -EINVAL;
+ }
+
+ if (clk_div > QSPI_CLK_DIV_MAX) {
+ dev_dbg(qspi->dev, "clock divider >%d , using /%d divider\n",
+ QSPI_CLK_DIV_MAX, QSPI_CLK_DIV_MAX + 1);
+ return -EINVAL;
+ }
+
+ dev_dbg(qspi->dev, "hz: %d, clock divider %d\n",
+ qspi->spi_max_frequency, clk_div);
+
+ ret = pm_runtime_get_sync(qspi->dev);
+ if (ret) {
+ dev_err(qspi->dev, "pm_runtime_get_sync() failed\n");
+ return ret;
+ }
+
+ clk_ctrl_reg = ti_qspi_read(qspi, QSPI_SPI_CLOCK_CNTRL_REG);
+
+ clk_ctrl_reg &= ~QSPI_CLK_EN;
+
+ /* disable SCLK */
+ ti_qspi_write(qspi, clk_ctrl_reg, QSPI_SPI_CLOCK_CNTRL_REG);
+
+ /* enable SCLK */
+ clk_mask = QSPI_CLK_EN | clk_div;
+ ti_qspi_write(qspi, clk_mask, QSPI_SPI_CLOCK_CNTRL_REG);
+ ctx_reg->clkctrl = clk_mask;
+
+ pm_runtime_mark_last_busy(qspi->dev);
+ ret = pm_runtime_put_autosuspend(qspi->dev);
+ if (ret < 0) {
+ dev_err(qspi->dev, "pm_runtime_put_autosuspend() failed\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+static void ti_qspi_restore_ctx(struct ti_qspi *qspi)
+{
+ struct ti_qspi_regs *ctx_reg = &qspi->ctx_reg;
+
+ ti_qspi_write(qspi, ctx_reg->clkctrl, QSPI_SPI_CLOCK_CNTRL_REG);
+}
+
+static int qspi_write_msg(struct ti_qspi *qspi, struct spi_transfer *t)
+{
+ int wlen, count, ret;
+ unsigned int cmd;
+ const u8 *txbuf;
+
+ txbuf = t->tx_buf;
+ cmd = qspi->cmd | QSPI_WR_SNGL;
+ count = t->len;
+ wlen = t->bits_per_word;
+
+ while (count) {
+ switch (wlen) {
+ case 8:
+ dev_dbg(qspi->dev, "tx cmd %08x dc %08x data %02x\n",
+ cmd, qspi->dc, *txbuf);
+ writeb(*txbuf, qspi->base + QSPI_SPI_DATA_REG);
+ ti_qspi_write(qspi, cmd, QSPI_SPI_CMD_REG);
+ ret = wait_for_completion_timeout(&qspi->transfer_complete,
+ QSPI_COMPLETION_TIMEOUT);
+ if (ret == 0) {
+ dev_err(qspi->dev, "write timed out\n");
+ return -ETIMEDOUT;
+ }
+ txbuf += 1;
+ count -= 1;
+ break;
+ case 16:
+ dev_dbg(qspi->dev, "tx cmd %08x dc %08x data %04x\n",
+ cmd, qspi->dc, *txbuf);
+ writew(*((u16 *)txbuf), qspi->base + QSPI_SPI_DATA_REG);
+ ti_qspi_write(qspi, cmd, QSPI_SPI_CMD_REG);
+ ret = wait_for_completion_timeout(&qspi->transfer_complete,
+ QSPI_COMPLETION_TIMEOUT);
+ if (ret == 0) {
+ dev_err(qspi->dev, "write timed out\n");
+ return -ETIMEDOUT;
+ }
+ txbuf += 2;
+ count -= 2;
+ break;
+ case 32:
+ dev_dbg(qspi->dev, "tx cmd %08x dc %08x data %08x\n",
+ cmd, qspi->dc, *txbuf);
+ writel(*((u32 *)txbuf), qspi->base + QSPI_SPI_DATA_REG);
+ ti_qspi_write(qspi, cmd, QSPI_SPI_CMD_REG);
+ ret = wait_for_completion_timeout(&qspi->transfer_complete,
+ QSPI_COMPLETION_TIMEOUT);
+ if (ret == 0) {
+ dev_err(qspi->dev, "write timed out\n");
+ return -ETIMEDOUT;
+ }
+ txbuf += 4;
+ count -= 4;
+ break;
+ }
+ }
+
+ return 0;
+}
+
+static int qspi_read_msg(struct ti_qspi *qspi, struct spi_transfer *t)
+{
+ int wlen, count, ret;
+ unsigned int cmd;
+ u8 *rxbuf;
+
+ rxbuf = t->rx_buf;
+ cmd = qspi->cmd | QSPI_RD_SNGL;
+ count = t->len;
+ wlen = t->bits_per_word;
+
+ while (count) {
+ dev_dbg(qspi->dev, "rx cmd %08x dc %08x\n", cmd, qspi->dc);
+ ti_qspi_write(qspi, cmd, QSPI_SPI_CMD_REG);
+ ret = wait_for_completion_timeout(&qspi->transfer_complete,
+ QSPI_COMPLETION_TIMEOUT);
+ if (ret == 0) {
+ dev_err(qspi->dev, "read timed out\n");
+ return -ETIMEDOUT;
+ }
+ switch (wlen) {
+ case 8:
+ *rxbuf = readb(qspi->base + QSPI_SPI_DATA_REG);
+ rxbuf += 1;
+ count -= 1;
+ break;
+ case 16:
+ *((u16 *)rxbuf) = readw(qspi->base + QSPI_SPI_DATA_REG);
+ rxbuf += 2;
+ count -= 2;
+ break;
+ case 32:
+ *((u32 *)rxbuf) = readl(qspi->base + QSPI_SPI_DATA_REG);
+ rxbuf += 4;
+ count -= 4;
+ break;
+ }
+ }
+
+ return 0;
+}
+
+static int qspi_transfer_msg(struct ti_qspi *qspi, struct spi_transfer *t)
+{
+ int ret;
+
+ if (t->tx_buf) {
+ ret = qspi_write_msg(qspi, t);
+ if (ret) {
+ dev_dbg(qspi->dev, "Error while writing\n");
+ return ret;
+ }
+ }
+
+ if (t->rx_buf) {
+ ret = qspi_read_msg(qspi, t);
+ if (ret) {
+ dev_dbg(qspi->dev, "Error while reading\n");
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+static int ti_qspi_start_transfer_one(struct spi_master *master,
+ struct spi_message *m)
+{
+ struct ti_qspi *qspi = spi_master_get_devdata(master);
+ struct spi_device *spi = m->spi;
+ struct spi_transfer *t;
+ int status = 0, ret;
+ int frame_length;
+
+ /* setup device control reg */
+ qspi->dc = 0;
+
+ if (spi->mode & SPI_CPHA)
+ qspi->dc |= QSPI_CKPHA(spi->chip_select);
+ if (spi->mode & SPI_CPOL)
+ qspi->dc |= QSPI_CKPOL(spi->chip_select);
+ if (spi->mode & SPI_CS_HIGH)
+ qspi->dc |= QSPI_CSPOL(spi->chip_select);
+
+ frame_length = (m->frame_length << 3) / spi->bits_per_word;
+
+ frame_length = clamp(frame_length, 0, QSPI_FRAME);
+
+ /* setup command reg */
+ qspi->cmd = 0;
+ qspi->cmd |= QSPI_EN_CS(spi->chip_select);
+ qspi->cmd |= QSPI_FLEN(frame_length);
+ qspi->cmd |= QSPI_WC_CMD_INT_EN;
+
+ ti_qspi_write(qspi, QSPI_WC_INT_EN, QSPI_INTR_ENABLE_SET_REG);
+ ti_qspi_write(qspi, qspi->dc, QSPI_SPI_DC_REG);
+
+ mutex_lock(&qspi->list_lock);
+
+ list_for_each_entry(t, &m->transfers, transfer_list) {
+ qspi->cmd |= QSPI_WLEN(t->bits_per_word);
+
+ ret = qspi_transfer_msg(qspi, t);
+ if (ret) {
+ dev_dbg(qspi->dev, "transfer message failed\n");
+ return -EINVAL;
+ }
+
+ m->actual_length += t->len;
+ }
+
+ mutex_unlock(&qspi->list_lock);
+
+ m->status = status;
+ spi_finalize_current_message(master);
+
+ ti_qspi_write(qspi, qspi->cmd | QSPI_INVAL, QSPI_SPI_CMD_REG);
+
+ return status;
+}
+
+static irqreturn_t ti_qspi_isr(int irq, void *dev_id)
+{
+ struct ti_qspi *qspi = dev_id;
+ u16 int_stat;
+
+ irqreturn_t ret = IRQ_HANDLED;
+
+ spin_lock(&qspi->lock);
+
+ int_stat = ti_qspi_read(qspi, QSPI_INTR_STATUS_ENABLED_CLEAR);
+ qspi->stat = ti_qspi_read(qspi, QSPI_SPI_STATUS_REG);
+
+ if (!int_stat) {
+ dev_dbg(qspi->dev, "No IRQ triggered\n");
+ ret = IRQ_NONE;
+ goto out;
+ }
+
+ ret = IRQ_WAKE_THREAD;
+
+ ti_qspi_write(qspi, QSPI_WC_INT_DISABLE, QSPI_INTR_ENABLE_CLEAR_REG);
+ ti_qspi_write(qspi, QSPI_WC_INT_DISABLE,
+ QSPI_INTR_STATUS_ENABLED_CLEAR);
+
+out:
+ spin_unlock(&qspi->lock);
+
+ return ret;
+}
+
+static irqreturn_t ti_qspi_threaded_isr(int this_irq, void *dev_id)
+{
+ struct ti_qspi *qspi = dev_id;
+ unsigned long flags;
+
+ spin_lock_irqsave(&qspi->lock, flags);
+
+ if (qspi->stat & WC)
+ complete(&qspi->transfer_complete);
+
+ spin_unlock_irqrestore(&qspi->lock, flags);
+
+ ti_qspi_write(qspi, QSPI_WC_INT_EN, QSPI_INTR_ENABLE_SET_REG);
+
+ return IRQ_HANDLED;
+}
+
+static int ti_qspi_runtime_resume(struct device *dev)
+{
+ struct ti_qspi *qspi;
+ struct spi_master *master;
+
+ master = dev_get_drvdata(dev);
+ qspi = spi_master_get_devdata(master);
+ ti_qspi_restore_ctx(qspi);
+
+ return 0;
+}
+
+static const struct of_device_id ti_qspi_match[] = {
+ {.compatible = "ti,dra7xxx-qspi" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, dra7xxx_qspi_match);
+
+static int ti_qspi_probe(struct platform_device *pdev)
+{
+ struct ti_qspi *qspi;
+ struct spi_master *master;
+ struct resource *r;
+ struct device_node *np = pdev->dev.of_node;
+ u32 max_freq;
+ int ret = 0, num_cs, irq;
+
+ master = spi_alloc_master(&pdev->dev, sizeof(*qspi));
+ if (!master)
+ return -ENOMEM;
+
+ master->mode_bits = SPI_CPOL | SPI_CPHA;
+
+ master->bus_num = -1;
+ master->flags = SPI_MASTER_HALF_DUPLEX;
+ master->setup = ti_qspi_setup;
+ master->auto_runtime_pm = true;
+ master->transfer_one_message = ti_qspi_start_transfer_one;
+ master->dev.of_node = pdev->dev.of_node;
+ master->bits_per_word_mask = BIT(32 - 1) | BIT(16 - 1) | BIT(8 - 1);
+
+ if (!of_property_read_u32(np, "num-cs", &num_cs))
+ master->num_chipselect = num_cs;
+
+ platform_set_drvdata(pdev, master);
+
+ qspi = spi_master_get_devdata(master);
+ qspi->master = master;
+ qspi->dev = &pdev->dev;
+
+ r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0) {
+ dev_err(&pdev->dev, "no irq resource?\n");
+ return irq;
+ }
+
+ spin_lock_init(&qspi->lock);
+ mutex_init(&qspi->list_lock);
+
+ qspi->base = devm_ioremap_resource(&pdev->dev, r);
+ if (IS_ERR(qspi->base)) {
+ ret = PTR_ERR(qspi->base);
+ goto free_master;
+ }
+
+ ret = devm_request_threaded_irq(&pdev->dev, irq, ti_qspi_isr,
+ ti_qspi_threaded_isr, 0,
+ dev_name(&pdev->dev), qspi);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "Failed to register ISR for IRQ %d\n",
+ irq);
+ goto free_master;
+ }
+
+ qspi->fclk = devm_clk_get(&pdev->dev, "fck");
+ if (IS_ERR(qspi->fclk)) {
+ ret = PTR_ERR(qspi->fclk);
+ dev_err(&pdev->dev, "could not get clk: %d\n", ret);
+ }
+
+ init_completion(&qspi->transfer_complete);
+
+ pm_runtime_use_autosuspend(&pdev->dev);
+ pm_runtime_set_autosuspend_delay(&pdev->dev, QSPI_AUTOSUSPEND_TIMEOUT);
+ pm_runtime_enable(&pdev->dev);
+
+ if (!of_property_read_u32(np, "spi-max-frequency", &max_freq))
+ qspi->spi_max_frequency = max_freq;
+
+ ret = spi_register_master(master);
+ if (ret)
+ goto free_master;
+
+ return 0;
+
+free_master:
+ spi_master_put(master);
+ return ret;
+}
+
+static int ti_qspi_remove(struct platform_device *pdev)
+{
+ struct ti_qspi *qspi = platform_get_drvdata(pdev);
+
+ spi_unregister_master(qspi->master);
+
+ return 0;
+}
+
+static const struct dev_pm_ops ti_qspi_pm_ops = {
+ .runtime_resume = ti_qspi_runtime_resume,
+};
+
+static struct platform_driver ti_qspi_driver = {
+ .probe = ti_qspi_probe,
+ .remove = ti_qspi_remove,
+ .driver = {
+ .name = "ti,dra7xxx-qspi",
+ .owner = THIS_MODULE,
+ .pm = &ti_qspi_pm_ops,
+ .of_match_table = ti_qspi_match,
+ }
+};
+
+module_platform_driver(ti_qspi_driver);
+
+MODULE_AUTHOR("Sourav Poddar <sourav.poddar@ti.com>");
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("TI QSPI controller driver");
projects / linux-drm-fsl-dcu.git / commitdiff