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    Subject[PATCH 4.1 046/102] spi: img-spfi: fix multiple calls to request gpio
    Date
    4.1-stable review patch.  If anyone has any objections, please let me know.

    ------------------

    From: Sifan Naeem <sifan.naeem@imgtec.com>

    commit b03ba9e314c12b2127243145b5c1f41b2408de62 upstream.

    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@imgtec.com>
    Signed-off-by: Mark Brown <broonie@kernel.org>
    Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

    ---
    drivers/spi/spi-img-spfi.c | 47 ++++++++++++++++++++++++++++++++++++++-------
    1 file changed, 40 insertions(+), 7 deletions(-)

    --- 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 +445,49 @@ static int img_spfi_unprepare(struct spi
    static int img_spfi_setup(struct spi_device *spi)
    {
    int ret;
    + struct img_spfi_device_data *spfi_data = spi_get_ctldata(spi);

    - 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",
    + 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,



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