[PATCH 1/2] spi: clps711x: Driver refactor
Alexander Shiyan
shc_work at mail.ru
Wed Jan 1 01:09:28 EST 2014
This is a complex patch for refactoring CLPS711X SPI driver.
Major changes:
- Eliminate <mach/hardware.h> usage.
- Devicetree support.
Since we do not have any platform users of this driver,
non-DT support is removed. DT users will be introduced later
once DT support for this platform will be completed.
Signed-off-by: Alexander Shiyan <shc_work at mail.ru>
---
drivers/spi/Kconfig | 2 +-
drivers/spi/spi-clps711x.c | 233 ++++++++++-------------------
include/linux/platform_data/spi-clps711x.h | 21 ---
3 files changed, 84 insertions(+), 172 deletions(-)
delete mode 100644 include/linux/platform_data/spi-clps711x.h
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index 81b96e5..54c7bb2a 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -150,7 +150,7 @@ config SPI_BUTTERFLY
config SPI_CLPS711X
tristate "CLPS711X host SPI controller"
- depends on ARCH_CLPS711X
+ depends on OF && (ARCH_CLPS711X || COMPILE_TEST)
help
This enables dedicated general purpose SPI/Microwire1-compatible
master mode interface (SSI1) for CLPS711X-based CPUs.
diff --git a/drivers/spi/spi-clps711x.c b/drivers/spi/spi-clps711x.c
index 6f03d7e..9d8eb39 100644
--- a/drivers/spi/spi-clps711x.c
+++ b/drivers/spi/spi-clps711x.c
@@ -1,7 +1,7 @@
/*
* CLPS711X SPI bus driver
*
- * Copyright (C) 2012 Alexander Shiyan <shc_work at mail.ru>
+ * Copyright (C) 2012-2014 Alexander Shiyan <shc_work at mail.ru>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
@@ -9,113 +9,77 @@
* (at your option) any later version.
*/
-#include <linux/io.h>
#include <linux/clk.h>
-#include <linux/init.h>
-#include <linux/gpio.h>
#include <linux/delay.h>
-#include <linux/module.h>
+#include <linux/gpio.h>
#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/mfd/syscon.h>
+#include <linux/mfd/syscon/clps711x.h>
#include <linux/spi/spi.h>
-#include <linux/platform_data/spi-clps711x.h>
-
-#include <mach/hardware.h>
-#define DRIVER_NAME "spi-clps711x"
+#define SYNCIO_FRMLEN(x) (((x) & 0x1f) << 8)
+#define SYNCIO_SMCKEN (1 << 13)
+#define SYNCIO_TXFRMEN (1 << 14)
struct spi_clps711x_data {
struct completion done;
-
+ void __iomem *syncio;
+ struct regmap *syscon3;
struct clk *spi_clk;
- u32 max_speed_hz;
-
u8 *tx_buf;
u8 *rx_buf;
- int count;
+ unsigned int bpw;
int len;
-
- int chipselect[0];
};
static int spi_clps711x_setup(struct spi_device *spi)
{
- struct spi_clps711x_data *hw = spi_master_get_devdata(spi->master);
+ if (!spi->controller_state) {
+ int ret;
- /* We are expect that SPI-device is not selected */
- gpio_direction_output(hw->chipselect[spi->chip_select],
- !(spi->mode & SPI_CS_HIGH));
+ ret = devm_gpio_request(&spi->master->dev, spi->cs_gpio, NULL);
+ if (ret)
+ return ret;
- return 0;
-}
-
-static void spi_clps711x_setup_mode(struct spi_device *spi)
-{
- /* Setup edge for transfer */
- if (spi->mode & SPI_CPHA)
- clps_writew(clps_readw(SYSCON3) | SYSCON3_ADCCKNSEN, SYSCON3);
- else
- clps_writew(clps_readw(SYSCON3) & ~SYSCON3_ADCCKNSEN, SYSCON3);
-}
-
-static int spi_clps711x_setup_xfer(struct spi_device *spi,
- struct spi_transfer *xfer)
-{
- u32 speed = xfer->speed_hz ? : spi->max_speed_hz;
- u8 bpw = xfer->bits_per_word;
- struct spi_clps711x_data *hw = spi_master_get_devdata(spi->master);
-
- if (bpw != 8) {
- dev_err(&spi->dev, "Unsupported master bus width %i\n", bpw);
- return -EINVAL;
+ spi->controller_state = spi;
}
- /* Setup SPI frequency divider */
- if (!speed || (speed >= hw->max_speed_hz))
- clps_writel((clps_readl(SYSCON1) & ~SYSCON1_ADCKSEL_MASK) |
- SYSCON1_ADCKSEL(3), SYSCON1);
- else if (speed >= (hw->max_speed_hz / 2))
- clps_writel((clps_readl(SYSCON1) & ~SYSCON1_ADCKSEL_MASK) |
- SYSCON1_ADCKSEL(2), SYSCON1);
- else if (speed >= (hw->max_speed_hz / 8))
- clps_writel((clps_readl(SYSCON1) & ~SYSCON1_ADCKSEL_MASK) |
- SYSCON1_ADCKSEL(1), SYSCON1);
- else
- clps_writel((clps_readl(SYSCON1) & ~SYSCON1_ADCKSEL_MASK) |
- SYSCON1_ADCKSEL(0), SYSCON1);
-
- return 0;
+ return gpio_direction_output(spi->cs_gpio, !(spi->mode & SPI_CS_HIGH));
}
static int spi_clps711x_transfer_one_message(struct spi_master *master,
struct spi_message *msg)
{
struct spi_clps711x_data *hw = spi_master_get_devdata(master);
+ struct spi_device *spi = msg->spi;
struct spi_transfer *xfer;
- int status = 0, cs = hw->chipselect[msg->spi->chip_select];
- u32 data;
- spi_clps711x_setup_mode(msg->spi);
+ /* Setup mode for transfer */
+ regmap_update_bits(hw->syscon3, SYSCON_OFFSET, SYSCON3_ADCCKNSEN,
+ (spi->mode & SPI_CPHA) ? SYSCON3_ADCCKNSEN : 0);
list_for_each_entry(xfer, &msg->transfers, transfer_list) {
- if (spi_clps711x_setup_xfer(msg->spi, xfer)) {
- status = -EINVAL;
- goto out_xfr;
- }
+ u8 data;
- gpio_set_value(cs, !!(msg->spi->mode & SPI_CS_HIGH));
+ clk_set_rate(hw->spi_clk, xfer->speed_hz ? : spi->max_speed_hz);
+
+ gpio_set_value(spi->cs_gpio, !!(spi->mode & SPI_CS_HIGH));
reinit_completion(&hw->done);
- hw->count = 0;
hw->len = xfer->len;
+ hw->bpw = xfer->bits_per_word ? : spi->bits_per_word;
hw->tx_buf = (u8 *)xfer->tx_buf;
hw->rx_buf = (u8 *)xfer->rx_buf;
/* Initiate transfer */
- data = hw->tx_buf ? hw->tx_buf[hw->count] : 0;
- clps_writel(data | SYNCIO_FRMLEN(8) | SYNCIO_TXFRMEN, SYNCIO);
-
+ data = hw->tx_buf ? *hw->tx_buf++ : 0;
+ writel(data | SYNCIO_FRMLEN(hw->bpw) | SYNCIO_TXFRMEN,
+ hw->syncio);
wait_for_completion(&hw->done);
if (xfer->delay_usecs)
@@ -123,13 +87,13 @@ static int spi_clps711x_transfer_one_message(struct spi_master *master,
if (xfer->cs_change ||
list_is_last(&xfer->transfer_list, &msg->transfers))
- gpio_set_value(cs, !(msg->spi->mode & SPI_CS_HIGH));
+ gpio_set_value(spi->cs_gpio,
+ !(spi->mode & SPI_CS_HIGH));
msg->actual_length += xfer->len;
}
-out_xfr:
- msg->status = status;
+ msg->status = 0;
spi_finalize_current_message(master);
return 0;
@@ -138,19 +102,18 @@ out_xfr:
static irqreturn_t spi_clps711x_isr(int irq, void *dev_id)
{
struct spi_clps711x_data *hw = (struct spi_clps711x_data *)dev_id;
- u32 data;
+ u8 data;
/* Handle RX */
- data = clps_readb(SYNCIO);
+ data = readb(hw->syncio);
if (hw->rx_buf)
- hw->rx_buf[hw->count] = (u8)data;
-
- hw->count++;
+ *hw->rx_buf++ = data;
/* Handle TX */
- if (hw->count < hw->len) {
- data = hw->tx_buf ? hw->tx_buf[hw->count] : 0;
- clps_writel(data | SYNCIO_FRMLEN(8) | SYNCIO_TXFRMEN, SYNCIO);
+ if (--hw->len > 0) {
+ data = hw->tx_buf ? *hw->tx_buf++ : 0;
+ writel(data | SYNCIO_FRMLEN(hw->bpw) | SYNCIO_TXFRMEN,
+ hw->syncio);
} else
complete(&hw->done);
@@ -159,116 +122,86 @@ static irqreturn_t spi_clps711x_isr(int irq, void *dev_id)
static int spi_clps711x_probe(struct platform_device *pdev)
{
- int i, ret;
- struct spi_master *master;
+ struct device_node *np = pdev->dev.of_node;
struct spi_clps711x_data *hw;
- struct spi_clps711x_pdata *pdata = dev_get_platdata(&pdev->dev);
+ struct spi_master *master;
+ struct resource *res;
+ int irq, ret;
- if (!pdata) {
- dev_err(&pdev->dev, "No platform data supplied\n");
- return -EINVAL;
- }
+ master = spi_alloc_master(&pdev->dev, sizeof(*hw));
+ if (!master)
+ return -ENOMEM;
- if (pdata->num_chipselect < 1) {
- dev_err(&pdev->dev, "At least one CS must be defined\n");
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0)
return -EINVAL;
- }
- master = spi_alloc_master(&pdev->dev,
- sizeof(struct spi_clps711x_data) +
- sizeof(int) * pdata->num_chipselect);
- if (!master) {
- dev_err(&pdev->dev, "SPI allocating memory error\n");
- return -ENOMEM;
+ hw = spi_master_get_devdata(master);
+
+ hw->spi_clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(hw->spi_clk)) {
+ ret = PTR_ERR(hw->spi_clk);
+ goto err_out;
}
- master->bus_num = pdev->id;
+ master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 8);
+ master->bus_num = -1;
+ master->dev.of_node = np;
master->mode_bits = SPI_CPHA | SPI_CS_HIGH;
- master->bits_per_word_mask = SPI_BPW_MASK(8);
- master->num_chipselect = pdata->num_chipselect;
master->setup = spi_clps711x_setup;
master->transfer_one_message = spi_clps711x_transfer_one_message;
- hw = spi_master_get_devdata(master);
-
- for (i = 0; i < master->num_chipselect; i++) {
- hw->chipselect[i] = pdata->chipselect[i];
- if (!gpio_is_valid(hw->chipselect[i])) {
- dev_err(&pdev->dev, "Invalid CS GPIO %i\n", i);
- ret = -EINVAL;
- goto err_out;
- }
- if (gpio_request(hw->chipselect[i], DRIVER_NAME)) {
- dev_err(&pdev->dev, "Can't get CS GPIO %i\n", i);
- ret = -EINVAL;
- goto err_out;
- }
+ hw->syscon3 = syscon_regmap_lookup_by_phandle(np, "syscon");
+ if (IS_ERR(hw->syscon3)) {
+ ret = PTR_ERR(hw->syscon3);
+ goto err_out;
}
- hw->spi_clk = devm_clk_get(&pdev->dev, "spi");
- if (IS_ERR(hw->spi_clk)) {
- dev_err(&pdev->dev, "Can't get clocks\n");
- ret = PTR_ERR(hw->spi_clk);
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ hw->syncio = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(hw->syncio)) {
+ ret = PTR_ERR(hw->syncio);
goto err_out;
}
- hw->max_speed_hz = clk_get_rate(hw->spi_clk);
init_completion(&hw->done);
- platform_set_drvdata(pdev, master);
/* Disable extended mode due hardware problems */
- clps_writew(clps_readw(SYSCON3) & ~SYSCON3_ADCCON, SYSCON3);
+ ret = regmap_update_bits(hw->syscon3, SYSCON_OFFSET, SYSCON3_ADCCON, 0);
+ if (ret)
+ goto err_out;
/* Clear possible pending interrupt */
- clps_readl(SYNCIO);
+ readl(hw->syncio);
- ret = devm_request_irq(&pdev->dev, IRQ_SSEOTI, spi_clps711x_isr, 0,
+ ret = devm_request_irq(&pdev->dev, irq, spi_clps711x_isr, 0,
dev_name(&pdev->dev), hw);
- if (ret) {
- dev_err(&pdev->dev, "Can't request IRQ\n");
+ if (ret)
goto err_out;
- }
ret = devm_spi_register_master(&pdev->dev, master);
- if (!ret) {
- dev_info(&pdev->dev,
- "SPI bus driver initialized. Master clock %u Hz\n",
- hw->max_speed_hz);
+ if (!ret)
return 0;
- }
-
- dev_err(&pdev->dev, "Failed to register master\n");
err_out:
- while (--i >= 0)
- if (gpio_is_valid(hw->chipselect[i]))
- gpio_free(hw->chipselect[i]);
-
spi_master_put(master);
return ret;
}
-static int spi_clps711x_remove(struct platform_device *pdev)
-{
- int i;
- struct spi_master *master = platform_get_drvdata(pdev);
- struct spi_clps711x_data *hw = spi_master_get_devdata(master);
-
- for (i = 0; i < master->num_chipselect; i++)
- if (gpio_is_valid(hw->chipselect[i]))
- gpio_free(hw->chipselect[i]);
-
- return 0;
-}
+static const struct of_device_id clps711x_spi_dt_ids[] = {
+ { .compatible = "cirrus,clps711x-spi", },
+ { }
+};
+MODULE_DEVICE_TABLE(of, clps711x_spi_dt_ids);
static struct platform_driver clps711x_spi_driver = {
.driver = {
- .name = DRIVER_NAME,
- .owner = THIS_MODULE,
+ .name = "clps711x-spi",
+ .owner = THIS_MODULE,
+ .of_match_table = clps711x_spi_dt_ids,
},
.probe = spi_clps711x_probe,
- .remove = spi_clps711x_remove,
};
module_platform_driver(clps711x_spi_driver);
diff --git a/include/linux/platform_data/spi-clps711x.h b/include/linux/platform_data/spi-clps711x.h
deleted file mode 100644
index 301956e..0000000
--- a/include/linux/platform_data/spi-clps711x.h
+++ /dev/null
@@ -1,21 +0,0 @@
-/*
- * CLPS711X SPI bus driver definitions
- *
- * Copyright (C) 2012 Alexander Shiyan <shc_work at mail.ru>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- */
-
-#ifndef ____LINUX_PLATFORM_DATA_SPI_CLPS711X_H
-#define ____LINUX_PLATFORM_DATA_SPI_CLPS711X_H
-
-/* Board specific platform_data */
-struct spi_clps711x_pdata {
- int *chipselect; /* Array of GPIO-numbers */
- int num_chipselect; /* Total count of GPIOs */
-};
-
-#endif
--
1.8.3.2
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