On 08/16/2012 10:05 PM, Thomas Abraham wrote:
> Add device tree based discovery support for Samsung's sdhci controller
> 
> Cc: Ben Dooks <ben-li...@fluff.org>
> Cc: Kukjin Kim <kgene....@samsung.com>
> Cc: Chris Ball <c...@laptop.org>
> Signed-off-by: Thomas Abraham <thomas.abra...@linaro.org>
> ---
> Changes since v3:
> 
> The patch series that adds device tree support for Samsung sdhci controller
> had six patches in total, of which, the first five patches have been accepted.
> The sixth patch in the series was dropped since it was using custom Samsung
> properties for descrbing the bus-width and card-detect gpio, but had otherwise
> addressed all the comments.
> 
> This patch reworks the sixth patch in v3 of the sdhci device tree support
> patch series. The only change in this patch from the v3 version is the use of
> generic mmc bindings for descrbing the bus-width and card-detect gpio.
> 
>  .../devicetree/bindings/mmc/samsung-sdhci.txt      |   51 +++++++
>  drivers/mmc/host/sdhci-s3c.c                       |  146 
> +++++++++++++++++++-
>  2 files changed, 191 insertions(+), 6 deletions(-)
>  create mode 100644 Documentation/devicetree/bindings/mmc/samsung-sdhci.txt
> 
> diff --git a/Documentation/devicetree/bindings/mmc/samsung-sdhci.txt 
> b/Documentation/devicetree/bindings/mmc/samsung-sdhci.txt
> new file mode 100644
> index 0000000..398540b
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mmc/samsung-sdhci.txt
> @@ -0,0 +1,51 @@
> +* Samsung's SDHCI Controller device tree bindings
> +
> +Samsung's SDHCI controller is used as a connectivity interface with external
> +MMC, SD and eMMC storage mediums. This file documents differences between the
> +core mmc properties described by mmc.txt and the properties used by the
> +Samsung implmentation of the SDHCI controller.
> +
> +Required SoC Specific Properties:
> +- compatible: should be one of the following
> +  - "samsung,s3c6410-sdhci": For controllers compatible with s3c6410 sdhci
> +    controller.
> +  - "samsung,exynos4210-sdhci": For controllers compatible with Exynos4 sdhci
> +    controller.
> +
> +Required Board Specific Properties:
> +- gpios: Should specify the gpios used for clock, command and data lines. The
> +  gpio specifier format depends on the gpio controller.
> +
> +Optional Board Specific Properties:
> +- One of the following properties for card detect type.
> +  - samsung,sdhci-cd-internal: Card detect line from the card slot  is
> +    connected to the card detect pad of the sdhci controller. A gpio is
> +    used for this connection (with possible pin function settings).
> +  - samsung,sdhci-cd-gpio: A gpio line (with possible pin function settings)
> +    is used a card detect line. This gpio line is not connected to card 
> detect
> +    pad of the sdhci controller.
> +  - samsung,sdhci-cd-none: There is no card detect line. Polling is used to
> +    detect the presence of the card. (DEFAULT, if no card detect property
> +    is specified).
> +  - samsung,sdhci-cd-permanent: There is no card detect line. The card is
> +    permanently connected to the sdhci controller.
> +
> +Example:
> +     sdhci@12530000 {
> +             compatible = "samsung,exynos4210-sdhci";
> +             reg = <0x12530000 0x100>;
> +             interrupts = <<0 75 0>;

Typo: interrupts = <0 75 0>;

> +             bus-width = <4>;
> +             samsung,sdhci-cd-internal;
> +             cd-gpios = <&gpk2 2 2 3 3>;
> +             gpios = <&gpk2 0 2 0 3>,  /* clock line */
> +                     <&gpk2 1 2 0 3>,  /* command line */
> +                     <&gpk2 3 2 3 3>,  /* data line 0 */
> +                     <&gpk2 4 2 3 3>,  /* data line 1 */
> +                     <&gpk2 5 2 3 3>,  /* data line 2 */
> +                     <&gpk2 6 2 3 3>;  /* data line 3 */
> +     };
> +
> +     Note: This example shows both SoC specific and board specific properties
> +     in a single device node. The properties can be actually be seperated
> +     into SoC specific node and board specific node.
> diff --git a/drivers/mmc/host/sdhci-s3c.c b/drivers/mmc/host/sdhci-s3c.c
> index a50c205..7fcc642 100644
> --- a/drivers/mmc/host/sdhci-s3c.c
> +++ b/drivers/mmc/host/sdhci-s3c.c
> @@ -34,6 +34,9 @@
>  
>  #define MAX_BUS_CLK  (4)
>  
> +/* Number of gpio's used is max data bus width + command and clock lines */
> +#define NUM_GPIOS(x) (x + 2)
> +
>  /**
>   * struct sdhci_s3c - S3C SDHCI instance
>   * @host: The SDHCI host created
> @@ -41,6 +44,7 @@
>   * @ioarea: The resource created when we claimed the IO area.
>   * @pdata: The platform data for this controller.
>   * @cur_clk: The index of the current bus clock.
> + * @gpios: List of gpio numbers parsed from device tree.
>   * @clk_io: The clock for the internal bus interface.
>   * @clk_bus: The clocks that are available for the SD/MMC bus clock.
>   */
> @@ -52,6 +56,7 @@ struct sdhci_s3c {
>       unsigned int            cur_clk;
>       int                     ext_cd_irq;
>       int                     ext_cd_gpio;
> +     int                     *gpios;
>  
>       struct clk              *clk_io;
>       struct clk              *clk_bus[MAX_BUS_CLK];
> @@ -419,9 +424,109 @@ static void sdhci_s3c_setup_card_detect_gpio(struct 
> sdhci_s3c *sc)
>       }
>  }
>  
> +#ifdef CONFIG_OF
> +static int __devinit sdhci_s3c_parse_dt(struct device *dev,
> +             struct sdhci_host *host, struct s3c_sdhci_platdata *pdata)
> +{
> +     struct device_node *node = dev->of_node;
> +     struct sdhci_s3c *ourhost = to_s3c(host);
> +     u32 max_width;
> +     int gpio, cnt, ret;
> +
> +     /* if the bus-width property is not specified, assume width as 1 */
> +     if (of_property_read_u32(node, "bus-width", &max_width))
> +             max_width = 1;
> +     pdata->max_width = max_width;
> +
> +     ourhost->gpios = devm_kzalloc(dev, NUM_GPIOS(pdata->max_width) *
> +                             sizeof(int), GFP_KERNEL);
> +     if (!ourhost->gpios)
> +             return -ENOMEM;
> +
> +     /* get the card detection method */
> +     if (of_get_property(node, "samsung,sdhci-cd-internal", NULL))
> +             pdata->cd_type = S3C_SDHCI_CD_INTERNAL;
> +     else if (of_get_property(node, "samsung,sdhci-cd-gpio", NULL))
> +             pdata->cd_type = S3C_SDHCI_CD_GPIO;
> +     else if (of_get_property(node, "samsung,sdhci-cd-none", NULL))
> +             pdata->cd_type = S3C_SDHCI_CD_NONE;
> +     else if (of_get_property(node, "samsung,sdhci-cd-permanent", NULL))
> +             pdata->cd_type = S3C_SDHCI_CD_PERMANENT;
> +     else
> +             pdata->cd_type = S3C_SDHCI_CD_NONE;
> +
> +     /* get the gpio used for card detection */
> +     if (pdata->cd_type == S3C_SDHCI_CD_GPIO ||
> +                     pdata->cd_type == S3C_SDHCI_CD_INTERNAL) {
> +             gpio = of_get_named_gpio(node, "cd-gpios", 0);
> +             if (!gpio_is_valid(gpio)) {
> +                     dev_err(dev, "invalid card detect gpio specified\n");
> +                     return -EINVAL;
> +             }
> +     }
> +
> +     if (pdata->cd_type == S3C_SDHCI_CD_GPIO) {
> +             pdata->ext_cd_gpio = gpio;
> +             ourhost->ext_cd_gpio = -1;
> +             if (of_get_property(node, "cd-inverted", NULL))
> +                     pdata->ext_cd_gpio_invert = 1;
> +     } else if (pdata->cd_type == S3C_SDHCI_CD_INTERNAL) {
> +             ret = gpio_request(gpio, "sdhci-cd");
> +             if (ret) {
> +                     dev_err(dev, "card detect gpio request failed\n");
> +                     return -EINVAL;
> +             }
> +             ourhost->ext_cd_gpio = gpio;
> +     }
> +
> +     /* get the gpios for command, clock and data lines */
> +     for (cnt = 0; cnt < NUM_GPIOS(pdata->max_width); cnt++) {
> +             gpio = of_get_gpio(node, cnt);
> +             if (!gpio_is_valid(gpio)) {
> +                     dev_err(dev, "invalid gpio[%d]\n", cnt);
> +                     goto err_free_dt_cd_gpio;
> +             }
> +             ourhost->gpios[cnt] = gpio;
> +     }
> +
> +     for (cnt = 0; cnt < NUM_GPIOS(pdata->max_width); cnt++) {
> +             ret = gpio_request(ourhost->gpios[cnt], "sdhci-gpio");
> +             if (ret) {
> +                     dev_err(dev, "gpio[%d] request failed\n", cnt);
> +                     goto err_free_dt_gpios;
> +             }
> +     }
> +
> +     return 0;
> +
> + err_free_dt_gpios:
> +     while (--cnt >= 0)
> +             gpio_free(ourhost->gpios[cnt]);
> + err_free_dt_cd_gpio:
> +     if (pdata->cd_type == S3C_SDHCI_CD_INTERNAL)
> +             gpio_free(ourhost->ext_cd_gpio);
> +     return -EINVAL;
> +}
> +#else
> +static int __devinit sdhci_s3c_parse_dt(struct device *dev,
> +             struct sdhci_host *host, struct s3c_sdhci_platdata *pdata)
> +{
> +     return -EINVAL;
> +}
> +#endif
> +
> +static const struct of_device_id sdhci_s3c_dt_match[];
> +
>  static inline struct sdhci_s3c_drv_data *sdhci_s3c_get_driver_data(
>                       struct platform_device *pdev)
>  {
> +#ifdef CONFIG_OF
> +     if (pdev->dev.of_node) {
> +             const struct of_device_id *match;
> +             match = of_match_node(sdhci_s3c_dt_match, pdev->dev.of_node);
> +             return (struct sdhci_s3c_drv_data *)match->data;
> +     }
> +#endif
>       return (struct sdhci_s3c_drv_data *)
>                       platform_get_device_id(pdev)->driver_data;
>  }
> @@ -436,7 +541,7 @@ static int __devinit sdhci_s3c_probe(struct 
> platform_device *pdev)
>       struct resource *res;
>       int ret, irq, ptr, clks;
>  
> -     if (!pdev->dev.platform_data) {
> +     if (!pdev->dev.platform_data && !pdev->dev.of_node) {
>               dev_err(dev, "no device data specified\n");
>               return -ENOENT;
>       }
> @@ -452,21 +557,28 @@ static int __devinit sdhci_s3c_probe(struct 
> platform_device *pdev)
>               dev_err(dev, "sdhci_alloc_host() failed\n");
>               return PTR_ERR(host);
>       }
> +     sc = sdhci_priv(host);
>  
>       pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
>       if (!pdata) {
>               ret = -ENOMEM;
> -             goto err_io_clk;
> +             goto err_pdata;
> +     }
> +
> +     if (pdev->dev.of_node) {
> +             ret = sdhci_s3c_parse_dt(&pdev->dev, host, pdata);
> +             if (ret)
> +                     goto err_pdata;
> +     } else {
> +             memcpy(pdata, pdev->dev.platform_data, sizeof(*pdata));
> +             sc->ext_cd_gpio = -1; /* invalid gpio number */
>       }
> -     memcpy(pdata, pdev->dev.platform_data, sizeof(*pdata));
>  
>       drv_data = sdhci_s3c_get_driver_data(pdev);
> -     sc = sdhci_priv(host);
>  
>       sc->host = host;
>       sc->pdev = pdev;
>       sc->pdata = pdata;
> -     sc->ext_cd_gpio = -1; /* invalid gpio number */
>  
>       platform_set_drvdata(pdev, host);
>  
> @@ -631,6 +743,12 @@ static int __devinit sdhci_s3c_probe(struct 
> platform_device *pdev)
>       clk_put(sc->clk_io);
>  
>   err_io_clk:
> +     for (ptr = 0; ptr < NUM_GPIOS(sc->pdata->max_width); ptr++)
> +             gpio_free(sc->gpios[ptr]);
> +     if (pdata->cd_type == S3C_SDHCI_CD_INTERNAL)
> +             gpio_free(sc->ext_cd_gpio);
> +
> + err_pdata:
>       sdhci_free_host(host);
>  
>       return ret;
> @@ -638,9 +756,9 @@ static int __devinit sdhci_s3c_probe(struct 
> platform_device *pdev)
>  
>  static int __devexit sdhci_s3c_remove(struct platform_device *pdev)
>  {
> -     struct s3c_sdhci_platdata *pdata = pdev->dev.platform_data;
>       struct sdhci_host *host =  platform_get_drvdata(pdev);
>       struct sdhci_s3c *sc = sdhci_priv(host);
> +     struct s3c_sdhci_platdata *pdata = sc->pdata;
>       int ptr;
>  
>       if (pdata->cd_type == S3C_SDHCI_CD_EXTERNAL && pdata->ext_cd_cleanup)
> @@ -665,6 +783,11 @@ static int __devexit sdhci_s3c_remove(struct 
> platform_device *pdev)
>       clk_disable(sc->clk_io);
>       clk_put(sc->clk_io);
>  
> +     if (pdev->dev.of_node) {
> +             for (ptr = 0; ptr < NUM_GPIOS(sc->pdata->max_width); ptr++)
> +                     gpio_free(sc->gpios[ptr]);
> +     }
> +
>       sdhci_free_host(host);
>       platform_set_drvdata(pdev, NULL);
>  
> @@ -737,6 +860,16 @@ static struct platform_device_id sdhci_s3c_driver_ids[] 
> = {
>  };
>  MODULE_DEVICE_TABLE(platform, sdhci_s3c_driver_ids);
>  
> +#ifdef CONFIG_OF
> +static const struct of_device_id sdhci_s3c_dt_match[] = {
> +     { .compatible = "samsung,s3c6410-sdhci", },
> +     { .compatible = "samsung,exynos4210-sdhci",
> +             .data = &exynos4_sdhci_drv_data },
> +     {},
> +};
> +MODULE_DEVICE_TABLE(of, sdhci_s3c_dt_match);
> +#endif
> +
>  static struct platform_driver sdhci_s3c_driver = {
>       .probe          = sdhci_s3c_probe,
>       .remove         = __devexit_p(sdhci_s3c_remove),
> @@ -744,6 +877,7 @@ static struct platform_driver sdhci_s3c_driver = {
>       .driver         = {
>               .owner  = THIS_MODULE,
>               .name   = "s3c-sdhci",
> +             .of_match_table = of_match_ptr(sdhci_s3c_dt_match),
>               .pm     = SDHCI_S3C_PMOPS,
>       },
>  };
> 


-- 
Tushar Behera
--
To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to