[PATCH v2] spi: mpc512x-psc: Convert to use GPIO descriptors

[PATCH v2] spi: mpc512x-psc: Convert to use GPIO descriptors

[Linus Walleij]

This driver is already relying on the core to provide
valid GPIO numbers in spi->cs_gpio through
of_spi_get_gpio_numbers(), so we can switch to letting
the core use GPIO descriptors instead.

The driver was assigning a local function to the custom
chipselect callback, but I chose to just open code the
gpiod setting instead, this is easier to read.

The only platform that overrides the cs_control callback
is the mpc832x_rdb.

Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Anatolij Gustschin <agust@denx.de>
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
---
ChangeLog v1->v2:
- Stop trying to use the core per-transfer CS handling,
  keep the old code intact around this and just deal with
  the GPIO descriptors.

I can't really compile any PPC code, I just hope I coded
this right...
---
 drivers/spi/spi-mpc512x-psc.c | 46 ++++++++++++++---------------------
 1 file changed, 18 insertions(+), 28 deletions(-)

diff --git a/drivers/spi/spi-mpc512x-psc.c b/drivers/spi/spi-mpc512x-psc.c
index 78a9bca8cc68..8a488d8e4c1b 100644
--- a/drivers/spi/spi-mpc512x-psc.c
+++ b/drivers/spi/spi-mpc512x-psc.c
@@ -23,7 +23,6 @@
 #include <linux/clk.h>
 #include <linux/spi/spi.h>
 #include <linux/fsl_devices.h>
-#include <linux/gpio.h>
 #include <asm/mpc52xx_psc.h>
 
 enum {
@@ -128,17 +127,28 @@ static void mpc512x_psc_spi_activate_cs(struct spi_device *spi)
 	out_be32(psc_addr(mps, ccr), ccr);
 	mps->bits_per_word = cs->bits_per_word;
 
-	if (mps->cs_control && gpio_is_valid(spi->cs_gpio))
-		mps->cs_control(spi, (spi->mode & SPI_CS_HIGH) ? 1 : 0);
+	if (cs->gpiod) {
+		if (mps->cs_control)
+			/* boardfile override */
+			mps->cs_control(spi, (spi->mode & SPI_CS_HIGH) ? 1 : 0);
+		else
+			/* gpiolib will deal with the inversion */
+			gpiod_set_value(spi->cs_gpiod, 1);
+	}
 }
 
 static void mpc512x_psc_spi_deactivate_cs(struct spi_device *spi)
 {
 	struct mpc512x_psc_spi *mps = spi_master_get_devdata(spi->master);
 
-	if (mps->cs_control && gpio_is_valid(spi->cs_gpio))
-		mps->cs_control(spi, (spi->mode & SPI_CS_HIGH) ? 0 : 1);
-
+	if (spi->cs_gpiod) {
+		if (mps->cs_control)
+			/* boardfile override */
+			mps->cs_control(spi, (spi->mode & SPI_CS_HIGH) ? 0 : 1);
+		else
+			/* gpiolib will deal with the inversion */
+			gpiod_set_value(spi->cs_gpiod, 0);
+	}
 }
 
 /* extract and scale size field in txsz or rxsz */
@@ -373,18 +383,6 @@ static int mpc512x_psc_spi_setup(struct spi_device *spi)
 		if (!cs)
 			return -ENOMEM;
 
-		if (gpio_is_valid(spi->cs_gpio)) {
-			ret = gpio_request(spi->cs_gpio, dev_name(&spi->dev));
-			if (ret) {
-				dev_err(&spi->dev, "can't get CS gpio: %d\n",
-					ret);
-				kfree(cs);
-				return ret;
-			}
-			gpio_direction_output(spi->cs_gpio,
-					spi->mode & SPI_CS_HIGH ? 0 : 1);
-		}
-
 		spi->controller_state = cs;
 	}
 
@@ -396,8 +394,6 @@ static int mpc512x_psc_spi_setup(struct spi_device *spi)
 
 static void mpc512x_psc_spi_cleanup(struct spi_device *spi)
 {
-	if (gpio_is_valid(spi->cs_gpio))
-		gpio_free(spi->cs_gpio);
 	kfree(spi->controller_state);
 }
 
@@ -476,11 +472,6 @@ static irqreturn_t mpc512x_psc_spi_isr(int irq, void *dev_id)
 	return IRQ_NONE;
 }
 
-static void mpc512x_spi_cs_control(struct spi_device *spi, bool onoff)
-{
-	gpio_set_value(spi->cs_gpio, onoff);
-}
-
 static int mpc512x_psc_spi_do_probe(struct device *dev, u32 regaddr,
 					      u32 size, unsigned int irq)
 {
@@ -500,9 +491,7 @@ static int mpc512x_psc_spi_do_probe(struct device *dev, u32 regaddr,
 	mps->type = (int)of_device_get_match_data(dev);
 	mps->irq = irq;
 
-	if (pdata == NULL) {
-		mps->cs_control = mpc512x_spi_cs_control;
-	} else {
+	if (pdata) {
 		mps->cs_control = pdata->cs_control;
 		master->bus_num = pdata->bus_num;
 		master->num_chipselect = pdata->max_chipselect;
@@ -513,6 +502,7 @@ static int mpc512x_psc_spi_do_probe(struct device *dev, u32 regaddr,
 	master->prepare_transfer_hardware = mpc512x_psc_spi_prep_xfer_hw;
 	master->transfer_one_message = mpc512x_psc_spi_msg_xfer;
 	master->unprepare_transfer_hardware = mpc512x_psc_spi_unprep_xfer_hw;
+	master->use_gpio_descriptors = true;
 	master->cleanup = mpc512x_psc_spi_cleanup;
 	master->dev.of_node = dev->of_node;
 
-- 
2.34.1

Re: [PATCH v2] spi: mpc512x-psc: Convert to use GPIO descriptors

[Mark Brown]

On Thu, 20 Jan 2022 01:26:00 +0100, Linus Walleij wrote:
> This driver is already relying on the core to provide
> valid GPIO numbers in spi->cs_gpio through
> of_spi_get_gpio_numbers(), so we can switch to letting
> the core use GPIO descriptors instead.
> 
> The driver was assigning a local function to the custom
> chipselect callback, but I chose to just open code the
> gpiod setting instead, this is easier to read.
> 
> [...]

Applied to

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git for-next

Thanks!

[1/1] spi: mpc512x-psc: Convert to use GPIO descriptors
      commit: 2818824ced4be5abc22c450340d548702f166d9a

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark