On 08/11/2016 at 18:48:52 +0100, Nicolas Ferre wrote :
> Use the managed gpio CS pin request so that we avoid having trouble
> in the cleanup code.
> In fact, if module was configured with DT, cleanup code released
> invalid pin. Since resource wasn't freed, module cannot be reinserted.
>
> This require to extract the gpio request call from the "setup" function
> and call it in the appropriate probe function.
>
> Reported-by: Alexander Morozov <[email protected]>
> Signed-off-by: Nicolas Ferre <[email protected]>
I think that's fine but I still have that item on my todo list
(discussion in july 2014 with Mark):
---
>> Mark: maybe it would make sense to do devm_gpio_request_one() in
>> of_spi_register_master(), after of_get_named_gpio.
> You need to transition all the drivers doing things manually but yes.
> As I keep saying all the GPIO handling needs to be completely
> refactored.
---
> ---
> v2: fix devm_gpio_request location: the setup code for device was not proper
> location. Move it to the probe function and add needed DT routines to
> handle all CS gpio specified.
>
> drivers/spi/spi-atmel.c | 50
> ++++++++++++++++++++++++++++++++++++++-----------
> 1 file changed, 39 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c
> index 32683a13dd60..a60925614480 100644
> --- a/drivers/spi/spi-atmel.c
> +++ b/drivers/spi/spi-atmel.c
> @@ -24,6 +24,7 @@
>
> #include <linux/io.h>
> #include <linux/gpio.h>
> +#include <linux/of_gpio.h>
> #include <linux/pinctrl/consumer.h>
> #include <linux/pm_runtime.h>
>
> @@ -1204,7 +1205,6 @@ static int atmel_spi_setup(struct spi_device *spi)
> u32 csr;
> unsigned int bits = spi->bits_per_word;
> unsigned int npcs_pin;
> - int ret;
>
> as = spi_master_get_devdata(spi->master);
>
> @@ -1247,16 +1247,9 @@ static int atmel_spi_setup(struct spi_device *spi)
> if (!asd)
> return -ENOMEM;
>
> - if (as->use_cs_gpios) {
> - ret = gpio_request(npcs_pin, dev_name(&spi->dev));
> - if (ret) {
> - kfree(asd);
> - return ret;
> - }
> -
> + if (as->use_cs_gpios)
> gpio_direction_output(npcs_pin,
> !(spi->mode & SPI_CS_HIGH));
> - }
>
> asd->npcs_pin = npcs_pin;
> spi->controller_state = asd;
> @@ -1471,13 +1464,11 @@ static int atmel_spi_transfer_one_message(struct
> spi_master *master,
> static void atmel_spi_cleanup(struct spi_device *spi)
> {
> struct atmel_spi_device *asd = spi->controller_state;
> - unsigned gpio = (unsigned long) spi->controller_data;
>
> if (!asd)
> return;
>
> spi->controller_state = NULL;
> - gpio_free(gpio);
> kfree(asd);
> }
>
> @@ -1499,6 +1490,39 @@ static void atmel_get_caps(struct atmel_spi *as)
> }
>
> /*-------------------------------------------------------------------------*/
> +static int atmel_spi_gpio_cs(struct platform_device *pdev)
> +{
> + struct spi_master *master = platform_get_drvdata(pdev);
> + struct atmel_spi *as = spi_master_get_devdata(master);
> + struct device_node *np = master->dev.of_node;
> + int i;
> + int ret = 0;
> + int nb = 0;
> +
> + if (!as->use_cs_gpios)
> + return 0;
> +
> + if (!np)
> + return 0;
> +
> + nb = of_gpio_named_count(np, "cs-gpios");
> + for (i = 0; i < nb; i++) {
> + int cs_gpio = of_get_named_gpio(pdev->dev.of_node,
> + "cs-gpios", i);
> +
> + if (cs_gpio == -EPROBE_DEFER)
> + return cs_gpio;
> +
> + if (gpio_is_valid(cs_gpio)) {
> + ret = devm_gpio_request(&pdev->dev, cs_gpio,
> + dev_name(&pdev->dev));
> + if (ret)
> + return ret;
> + }
> + }
> +
> + return 0;
> +}
>
> static int atmel_spi_probe(struct platform_device *pdev)
> {
> @@ -1577,6 +1601,10 @@ static int atmel_spi_probe(struct platform_device
> *pdev)
> master->num_chipselect = 4;
> }
>
> + ret = atmel_spi_gpio_cs(pdev);
> + if (ret)
> + goto out_unmap_regs;
> +
> as->use_dma = false;
> as->use_pdc = false;
> if (as->caps.has_dma_support) {
> --
> 2.9.0
>
--
Alexandre Belloni, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com
