RE: [PATCH] spi: img-spfi: fix multiple calls to request gpio

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Please ignore this patch.

Thanks,
Sifan

> -----Original Message-----
> From: Sifan Naeem
> Sent: 29 July 2015 11:44
> To: Mark Brown
> Cc: linux-spi@xxxxxxxxxxxxxxx; abrestic@xxxxxxxxxxxx;
> stable@xxxxxxxxxxxxxxx; Ezequiel Garcia; Sifan Naeem
> Subject: [PATCH] spi: img-spfi: fix multiple calls to request gpio
> 
> spfi_setup may be called many times by the spi framework, but
> gpio_request_one can only be called once without freeing, repeatedly calling
> gpio_request_one will cause an error to be thrown, which causes the
> request to spi_setup to be marked as failed.
> 
> We can have a per-spi_device flag that indicates whether or not the gpio has
> been requested. If the gpio has already been requested use
> gpio_direction_output to set the direction of the gpio.
> 
> Fixes: 8c2c8c03cdcb ("spi: img-spfi: Control CS lines with GPIO")
> Signed-off-by: Sifan Naeem <sifan.naeem@xxxxxxxxxx>
> Cc: <stable@xxxxxxxxxxxxxxx> # 4.1+
> ---
>  drivers/spi/spi-img-spfi.c |   50
> ++++++++++++++++++++++++++++++++++++--------
>  1 file changed, 41 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/spi/spi-img-spfi.c b/drivers/spi/spi-img-spfi.c index
> f27d9d5531b5..5dc57ee293e1 100644
> --- a/drivers/spi/spi-img-spfi.c
> +++ b/drivers/spi/spi-img-spfi.c
> @@ -105,6 +105,10 @@ struct img_spfi {
>  	bool rx_dma_busy;
>  };
> 
> +struct img_spfi_device_data {
> +    bool gpio_requested;
> +};
> +
>  static inline u32 spfi_readl(struct img_spfi *spfi, u32 reg)  {
>  	return readl(spfi->regs + reg);
> @@ -441,20 +445,48 @@ static int img_spfi_unprepare(struct spi_master
> *master,  static int img_spfi_setup(struct spi_device *spi)  {
>  	int ret;
> -
> -	ret = gpio_request_one(spi->cs_gpio, (spi->mode & SPI_CS_HIGH) ?
> -			       GPIOF_OUT_INIT_LOW : GPIOF_OUT_INIT_HIGH,
> -			       dev_name(&spi->dev));
> -	if (ret)
> -		dev_err(&spi->dev, "can't request chipselect gpio %d\n",
> -				spi->cs_gpio);
> -
> +	struct img_spfi_device_data *spfi_data = spi_get_ctldata(spi);
> +
> +	if (!spfi_data) {
> +		spfi_data = kzalloc(sizeof(*spfi_data), GFP_KERNEL);
> +		if (!spfi_data)
> +			return -ENOMEM;
> +		spfi_data->gpio_requested = false;
> +		spi_set_ctldata(spi, spfi_data);
> +	}
> +	if (!spfi_data->gpio_requested) {
> +		ret = gpio_request_one(spi->cs_gpio, (spi->mode &
> SPI_CS_HIGH) ?
> +					   GPIOF_OUT_INIT_LOW :
> GPIOF_OUT_INIT_HIGH,
> +					   dev_name(&spi->dev));
> +		if (ret)
> +			dev_err(&spi->dev, "can't request chipselect gpio
> %d\n",
> +					spi->cs_gpio);
> +		else
> +			spfi_data->gpio_requested = true;
> +	} else {
> +		if (gpio_is_valid(spi->cs_gpio)) {
> +			int mode = ((spi->mode & SPI_CS_HIGH) ?
> +					 GPIOF_OUT_INIT_LOW :
> GPIOF_OUT_INIT_HIGH);
> +
> +			ret = gpio_direction_output(spi->cs_gpio, mode);
> +			if (ret)
> +				dev_err(&spi->dev, "chipselect gpio %d
> setup failed (%d)\n",
> +					spi->cs_gpio, ret);
> +		}
> +	}
>  	return ret;
>  }
> 
>  static void img_spfi_cleanup(struct spi_device *spi)  {
> -	gpio_free(spi->cs_gpio);
> +	struct img_spfi_device_data *spfi_data = spi_get_ctldata(spi);
> +
> +	if (spfi_data) {
> +		if (spfi_data->gpio_requested)
> +			gpio_free(spi->cs_gpio);
> +		kfree(spfi_data);
> +		spi_set_ctldata(spi, NULL);
> +	}
>  }
> 
>  static void img_spfi_config(struct spi_master *master, struct spi_device
> *spi,
> --
> 1.7.9.5

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