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Subject[PATCH V2 5/8] spi: lpspi: use the core way to implement cs-gpio function
Date
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>
---
V2:
- use core way to implement cs-gpio control. Removed the redundant code
in the driver.
---
drivers/spi/spi-fsl-lpspi.c | 101 +++++++++++++++++++++++-------------
1 file changed, 66 insertions(+), 35 deletions(-)

diff --git a/drivers/spi/spi-fsl-lpspi.c b/drivers/spi/spi-fsl-lpspi.c
index 69635cde0e22..a25e0e03f058 100644
--- 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;
--
2.17.1
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