spi: spi-ep93xx: simplify GPIO chip selects

This driver requires a GPIO line to be used for the chip select of
each SPI device.

Remove the ep93xx_spi_chip_ops definition from the platform data
and use the spi core GPIO handling for the chip selects.

Fix all the ep93xx platforms that use this driver and remove the
old Documentation.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

1 files changed, 44 insertions, 95 deletions

diff --git a/drivers/spi/spi-ep93xx.c b/drivers/spi/spi-ep93xx.c
index 17a6387e20b5..b5d766064b7b 100644
--- a/drivers/spi/spi-ep93xx.c
+++ b/drivers/spi/spi-ep93xx.c
@@ -28,6 +28,7 @@
 #include <linux/platform_device.h>
 #include <linux/sched.h>
 #include <linux/scatterlist.h>
+#include <linux/gpio.h>
 #include <linux/spi/spi.h>
 
 #include <linux/platform_data/dma-ep93xx.h>
@@ -107,16 +108,6 @@ struct ep93xx_spi {
         void                            *zeropage;
 };
 
-/**
- * struct ep93xx_spi_chip - SPI device hardware settings
- * @spi: back pointer to the SPI device
- * @ops: private chip operations
- */
-struct ep93xx_spi_chip {
-        const struct spi_device         *spi;
-        struct ep93xx_spi_chip_ops      *ops;
-};
-
 /* converts bits per word to CR0.DSS value */
 #define bits_per_word_to_dss(bpw)       ((bpw) - 1)
 
@@ -229,104 +220,36 @@ static int ep93xx_spi_calc_divisors(const struct ep93xx_spi *espi,
         return -EINVAL;
 }
 
-static void ep93xx_spi_cs_control(struct spi_device *spi, bool control)
-{
-        struct ep93xx_spi_chip *chip = spi_get_ctldata(spi);
-        int value = (spi->mode & SPI_CS_HIGH) ? control : !control;
-
-        if (chip->ops && chip->ops->cs_control)
-                chip->ops->cs_control(spi, value);
-}
-
-/**
- * ep93xx_spi_setup() - setup an SPI device
- * @spi: SPI device to setup
- *
- * This function sets up SPI device mode, speed etc. Can be called multiple
- * times for a single device. Returns %0 in case of success, negative error in
- * case of failure. When this function returns success, the device is
- * deselected.
- */
-static int ep93xx_spi_setup(struct spi_device *spi)
+static void ep93xx_spi_cs_control(struct spi_device *spi, bool enable)
 {
-        struct ep93xx_spi *espi = spi_master_get_devdata(spi->master);
-        struct ep93xx_spi_chip *chip;
+        if (spi->mode & SPI_CS_HIGH)
+                enable = !enable;
 
-        chip = spi_get_ctldata(spi);
-        if (!chip) {
-                dev_dbg(&espi->pdev->dev, "initial setup for %s\n",
-                        spi->modalias);
-
-                chip = kzalloc(sizeof(*chip), GFP_KERNEL);
-                if (!chip)
-                        return -ENOMEM;
-
-                chip->spi = spi;
-                chip->ops = spi->controller_data;
-
-                if (chip->ops && chip->ops->setup) {
-                        int ret = chip->ops->setup(spi);
-
-                        if (ret) {
-                                kfree(chip);
-                                return ret;
-                        }
-                }
-
-                spi_set_ctldata(spi, chip);
-        }
-
-        ep93xx_spi_cs_control(spi, false);
-        return 0;
+        if (gpio_is_valid(spi->cs_gpio))
+                gpio_set_value(spi->cs_gpio, !enable);
 }
 
-/**
- * ep93xx_spi_cleanup() - cleans up master controller specific state
- * @spi: SPI device to cleanup
- *
- * This function releases master controller specific state for given @spi
- * device.
- */
-static void ep93xx_spi_cleanup(struct spi_device *spi)
-{
-        struct ep93xx_spi_chip *chip;
-
-        chip = spi_get_ctldata(spi);
-        if (chip) {
-                if (chip->ops && chip->ops->cleanup)
-                        chip->ops->cleanup(spi);
-                spi_set_ctldata(spi, NULL);
-                kfree(chip);
-        }
-}
-
-/**
- * ep93xx_spi_chip_setup() - configures hardware according to given @chip
- * @espi: ep93xx SPI controller struct
- * @chip: chip specific settings
- * @speed_hz: transfer speed
- * @bits_per_word: transfer bits_per_word
- */
 static int ep93xx_spi_chip_setup(const struct ep93xx_spi *espi,
-                                 const struct ep93xx_spi_chip *chip,
-                                 u32 speed_hz, u8 bits_per_word)
+                                 struct spi_device *spi,
+                                 struct spi_transfer *xfer)
 {
-        u8 dss = bits_per_word_to_dss(bits_per_word);
+        u8 dss = bits_per_word_to_dss(xfer->bits_per_word);
         u8 div_cpsr = 0;
         u8 div_scr = 0;
         u16 cr0;
         int err;
 
-        err = ep93xx_spi_calc_divisors(espi, speed_hz, &div_cpsr, &div_scr);
+        err = ep93xx_spi_calc_divisors(espi, xfer->speed_hz,
+                                       &div_cpsr, &div_scr);
         if (err)
                 return err;
 
         cr0 = div_scr << SSPCR0_SCR_SHIFT;
-        cr0 |= (chip->spi->mode & (SPI_CPHA|SPI_CPOL)) << SSPCR0_MODE_SHIFT;
+        cr0 |= (spi->mode & (SPI_CPHA | SPI_CPOL)) << SSPCR0_MODE_SHIFT;
         cr0 |= dss;
 
         dev_dbg(&espi->pdev->dev, "setup: mode %d, cpsr %d, scr %d, dss %d\n",
-                chip->spi->mode, div_cpsr, div_scr, dss);
+                spi->mode, div_cpsr, div_scr, dss);
         dev_dbg(&espi->pdev->dev, "setup: cr0 %#x\n", cr0);
 
         ep93xx_spi_write_u8(espi, SSPCPSR, div_cpsr);
@@ -603,12 +526,11 @@ static void ep93xx_spi_process_transfer(struct ep93xx_spi *espi,
                                         struct spi_message *msg,
                                         struct spi_transfer *t)
 {
-        struct ep93xx_spi_chip *chip = spi_get_ctldata(msg->spi);
         int err;
 
         msg->state = t;
 
-        err = ep93xx_spi_chip_setup(espi, chip, t->speed_hz, t->bits_per_word);
+        err = ep93xx_spi_chip_setup(espi, msg->spi, t);
         if (err) {
                 dev_err(&espi->pdev->dev,
                         "failed to setup chip for transfer\n");
@@ -863,8 +785,13 @@ static int ep93xx_spi_probe(struct platform_device *pdev)
         struct resource *res;
         int irq;
         int error;
+        int i;
 
         info = dev_get_platdata(&pdev->dev);
+        if (!info) {
+                dev_err(&pdev->dev, "missing platform data\n");
+                return -EINVAL;
+        }
 
         irq = platform_get_irq(pdev, 0);
         if (irq < 0) {
@@ -882,14 +809,36 @@ static int ep93xx_spi_probe(struct platform_device *pdev)
         if (!master)
                 return -ENOMEM;
 
-        master->setup = ep93xx_spi_setup;
         master->transfer_one_message = ep93xx_spi_transfer_one_message;
-        master->cleanup = ep93xx_spi_cleanup;
         master->bus_num = pdev->id;
-        master->num_chipselect = info->num_chipselect;
         master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
         master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 16);
 
+        master->num_chipselect = info->num_chipselect;
+        master->cs_gpios = devm_kzalloc(&master->dev,
+                                        sizeof(int) * master->num_chipselect,
+                                        GFP_KERNEL);
+        if (!master->cs_gpios) {
+                error = -ENOMEM;
+                goto fail_release_master;
+        }
+
+        for (i = 0; i < master->num_chipselect; i++) {
+                master->cs_gpios[i] = info->chipselect[i];
+
+                if (!gpio_is_valid(master->cs_gpios[i]))
+                        continue;
+
+                error = devm_gpio_request_one(&pdev->dev, master->cs_gpios[i],
+                                              GPIOF_OUT_INIT_HIGH,
+                                              "ep93xx-spi");
+                if (error) {
+                        dev_err(&pdev->dev, "could not request cs gpio %d\n",
+                                master->cs_gpios[i]);
+                        goto fail_release_master;
+                }
+        }
+
         platform_set_drvdata(pdev, master);
 
         espi = spi_master_get_devdata(master);