spi: lpspi: use the core way to implement cs-gpio function

Use the default implementation of transfer_one_msg/chipselect/setup
functions in spi core to implement cs-gpio control.
Use fsl_lpspi_prepare_message to init the cs_gpio pin.

Signed-off-by: Clark Wang <xiaoning.wang@nxp.com>
Acked-by: Fugang Duan <Fugang.duan@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/drivers/spi/spi-fsl-lpspi.c b/drivers/spi/spi-fsl-lpspi.c
index 69635cd..a25e0e0 100644 (file)
--- a/drivers/spi/spi-fsl-lpspi.c
+++ b/drivers/spi/spi-fsl-lpspi.c
@@ -9,6 +9,7 @@
 #include <linux/completion.h>
 #include <linux/delay.h>
 #include <linux/err.h>
+#include <linux/gpio.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
 #include <linux/irq.h>
@@ -16,8 +17,10 @@
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/of_device.h>
+#include <linux/of_gpio.h>
 #include <linux/pinctrl/consumer.h>
 #include <linux/platform_device.h>
+#include <linux/platform_data/spi-imx.h>
 #include <linux/pm_runtime.h>
 #include <linux/slab.h>
 #include <linux/spi/spi.h>
@@ -91,6 +94,7 @@ struct fsl_lpspi_data {
        struct clk *clk_ipg;
        struct clk *clk_per;
        bool is_slave;
+       bool is_first_byte;
 
        void *rx_buf;
        const void *tx_buf;
@@ -106,6 +110,8 @@ struct fsl_lpspi_data {
        struct completion xfer_done;
 
        bool slave_aborted;
+
+       int chipselect[0];
 };
 
 static const struct of_device_id fsl_lpspi_dt_ids[] = {
@@ -178,6 +184,20 @@ static int lpspi_unprepare_xfer_hardware(struct spi_controller *controller)
        return 0;
 }
 
+static int fsl_lpspi_prepare_message(struct spi_controller *controller,
+                                    struct spi_message *msg)
+{
+       struct fsl_lpspi_data *fsl_lpspi =
+                                       spi_controller_get_devdata(controller);
+       struct spi_device *spi = msg->spi;
+       int gpio = fsl_lpspi->chipselect[spi->chip_select];
+
+       if (gpio_is_valid(gpio))
+               gpio_direction_output(gpio, spi->mode & SPI_CS_HIGH ? 0 : 1);
+
+       return 0;
+}
+
 static void fsl_lpspi_write_tx_fifo(struct fsl_lpspi_data *fsl_lpspi)
 {
        u8 txfifo_cnt;
@@ -210,8 +230,7 @@ static void fsl_lpspi_read_rx_fifo(struct fsl_lpspi_data *fsl_lpspi)
                fsl_lpspi->rx(fsl_lpspi);
 }
 
-static void fsl_lpspi_set_cmd(struct fsl_lpspi_data *fsl_lpspi,
-                             bool is_first_xfer)
+static void fsl_lpspi_set_cmd(struct fsl_lpspi_data *fsl_lpspi)
 {
        u32 temp = 0;
 
@@ -227,7 +246,7 @@ static void fsl_lpspi_set_cmd(struct fsl_lpspi_data *fsl_lpspi,
                 * For subsequent transfer, set TCR_CONTC to keep SS asserted.
                 */
                temp |= TCR_CONT;
-               if (is_first_xfer)
+               if (fsl_lpspi->is_first_byte)
                        temp &= ~TCR_CONTC;
                else
                        temp |= TCR_CONTC;
@@ -396,8 +415,7 @@ static int fsl_lpspi_reset(struct fsl_lpspi_data *fsl_lpspi)
        return 0;
 }
 
-static int fsl_lpspi_transfer_one(struct spi_controller *controller,
-                                 struct spi_device *spi,
+static int fsl_lpspi_pio_transfer(struct spi_controller *controller,
                                  struct spi_transfer *t)
 {
        struct fsl_lpspi_data *fsl_lpspi =
@@ -422,40 +440,27 @@ static int fsl_lpspi_transfer_one(struct spi_controller *controller,
        return 0;
 }
 
-static int fsl_lpspi_transfer_one_msg(struct spi_controller *controller,
-                                     struct spi_message *msg)
+static int fsl_lpspi_transfer_one(struct spi_controller *controller,
+                                 struct spi_device *spi,
+                                 struct spi_transfer *t)
 {
        struct fsl_lpspi_data *fsl_lpspi =
-                               spi_controller_get_devdata(controller);
-       struct spi_device *spi = msg->spi;
-       struct spi_transfer *xfer;
-       bool is_first_xfer = true;
-       int ret = 0;
-
-       msg->status = 0;
-       msg->actual_length = 0;
-
-       list_for_each_entry(xfer, &msg->transfers, transfer_list) {
-               ret = fsl_lpspi_setup_transfer(spi, xfer);
-               if (ret < 0)
-                       goto complete;
-
-               fsl_lpspi_set_cmd(fsl_lpspi, is_first_xfer);
-
-               is_first_xfer = false;
+                                       spi_controller_get_devdata(controller);
+       int ret;
 
-               ret = fsl_lpspi_transfer_one(controller, spi, xfer);
-               if (ret < 0)
-                       goto complete;
+       fsl_lpspi->is_first_byte = true;
+       ret = fsl_lpspi_setup_transfer(spi, t);
+       if (ret < 0)
+               return ret;
 
-               msg->actual_length += xfer->len;
-       }
+       fsl_lpspi_set_cmd(fsl_lpspi);
+       fsl_lpspi->is_first_byte = false;
 
-complete:
-       msg->status = ret;
-       spi_finalize_current_message(controller);
+       ret = fsl_lpspi_pio_transfer(controller, t);
+       if (ret < 0)
+               return ret;
 
-       return ret;
+       return 0;
 }
 
 static irqreturn_t fsl_lpspi_isr(int irq, void *dev_id)
@@ -531,10 +536,13 @@ static int fsl_lpspi_init_rpm(struct fsl_lpspi_data *fsl_lpspi)
 
 static int fsl_lpspi_probe(struct platform_device *pdev)
 {
+       struct device_node *np = pdev->dev.of_node;
        struct fsl_lpspi_data *fsl_lpspi;
        struct spi_controller *controller;
+       struct spi_imx_master *lpspi_platform_info =
+               dev_get_platdata(&pdev->dev);
        struct resource *res;
-       int ret, irq;
+       int i, ret, irq;
        u32 temp;
 
        if (of_property_read_bool((&pdev->dev)->of_node, "spi-slave"))
@@ -558,7 +566,30 @@ static int fsl_lpspi_probe(struct platform_device *pdev)
        fsl_lpspi->is_slave = of_property_read_bool((&pdev->dev)->of_node,
                                                    "spi-slave");
 
-       controller->transfer_one_message = fsl_lpspi_transfer_one_msg;
+       if (!fsl_lpspi->is_slave) {
+               for (i = 0; i < controller->num_chipselect; i++) {
+                       int cs_gpio = of_get_named_gpio(np, "cs-gpios", i);
+
+                       if (!gpio_is_valid(cs_gpio) && lpspi_platform_info)
+                               cs_gpio = lpspi_platform_info->chipselect[i];
+
+                       fsl_lpspi->chipselect[i] = cs_gpio;
+                       if (!gpio_is_valid(cs_gpio))
+                               continue;
+
+                       ret = devm_gpio_request(&pdev->dev,
+                                               fsl_lpspi->chipselect[i],
+                                               DRIVER_NAME);
+                       if (ret) {
+                               dev_err(&pdev->dev, "can't get cs gpios\n");
+                               goto out_controller_put;
+                       }
+               }
+               controller->cs_gpios = fsl_lpspi->chipselect;
+               controller->prepare_message = fsl_lpspi_prepare_message;
+       }
+
+       controller->transfer_one = fsl_lpspi_transfer_one;
        controller->prepare_transfer_hardware = lpspi_prepare_xfer_hardware;
        controller->unprepare_transfer_hardware = lpspi_unprepare_xfer_hardware;
        controller->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;