diff options
author | Thomas Abraham <thomas.abraham@linaro.org> | 2012-08-23 17:10:09 +0000 |
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committer | Chris Ball <cjb@laptop.org> | 2012-10-03 10:05:20 -0400 |
commit | cd1b00eb24b0b204303211df7ffd1a77a1005824 (patch) | |
tree | 25a53a69d00105217aa7485d42ffb099a9f08151 | |
parent | c3665006eccd7d2326b7dc2c1d5ff2f545dee6c5 (diff) | |
download | linux-stable-cd1b00eb24b0b204303211df7ffd1a77a1005824.tar.gz linux-stable-cd1b00eb24b0b204303211df7ffd1a77a1005824.tar.bz2 linux-stable-cd1b00eb24b0b204303211df7ffd1a77a1005824.zip |
mmc: sdhci-s3c: Add device tree support
Add device tree based discovery support for Samsung's sdhci controller.
Cc: Ben Dooks <ben-linux@fluff.org>
Cc: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Thomas Abraham <thomas.abraham@linaro.org>
Reviewed-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
-rw-r--r-- | Documentation/devicetree/bindings/mmc/samsung-sdhci.txt | 53 | ||||
-rw-r--r-- | drivers/mmc/host/sdhci-s3c.c | 158 |
2 files changed, 205 insertions, 6 deletions
diff --git a/Documentation/devicetree/bindings/mmc/samsung-sdhci.txt b/Documentation/devicetree/bindings/mmc/samsung-sdhci.txt new file mode 100644 index 000000000000..630a7d7f4718 --- /dev/null +++ b/Documentation/devicetree/bindings/mmc/samsung-sdhci.txt @@ -0,0 +1,53 @@ +* 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. + +Note: The mmc core bindings documentation states that if none of the core +card-detect bindings are used, then the standard sdhci card detect mechanism +is used. The Samsung's SDHCI controller bindings extends this as listed below. + +[A] The property "samsung,cd-pinmux-gpio" can be used as stated in the + "Optional Board Specific Properties" section below. + +[B] If core card-detect bindings and "samsung,cd-pinmux-gpio" property + is not specified, it is assumed that there is no card detection + mechanism used. + +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: +- samsung,cd-pinmux-gpio: Specifies the card detect line that is routed + through a pinmux to the card-detect pin of the card slot. This property + should be used only if none of the mmc core card-detect properties are + used. + +Example: + sdhci@12530000 { + compatible = "samsung,exynos4210-sdhci"; + reg = <0x12530000 0x100>; + interrupts = <0 75 0>; + bus-width = <4>; + 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 00969ba03277..0c77b10d2619 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]; @@ -422,9 +427,121 @@ 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, "broken-cd", 0)) { + pdata->cd_type = S3C_SDHCI_CD_NONE; + goto setup_bus; + } + + if (of_get_property(node, "non-removable", 0)) { + pdata->cd_type = S3C_SDHCI_CD_PERMANENT; + goto setup_bus; + } + + gpio = of_get_named_gpio(node, "cd-gpios", 0); + if (gpio_is_valid(gpio)) { + pdata->cd_type = S3C_SDHCI_CD_GPIO; + goto found_cd; + } else if (gpio != -ENOENT) { + dev_err(dev, "invalid card detect gpio specified\n"); + return -EINVAL; + } + + gpio = of_get_named_gpio(node, "samsung,cd-pinmux-gpio", 0); + if (gpio_is_valid(gpio)) { + pdata->cd_type = S3C_SDHCI_CD_INTERNAL; + goto found_cd; + } else if (gpio != -ENOENT) { + dev_err(dev, "invalid card detect gpio specified\n"); + return -EINVAL; + } + + dev_info(dev, "assuming no card detect line available\n"); + pdata->cd_type = S3C_SDHCI_CD_NONE; + + found_cd: + 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; + } + + setup_bus: + /* 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; } @@ -439,7 +556,7 @@ 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; } @@ -455,21 +572,28 @@ 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); @@ -633,6 +757,12 @@ 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; @@ -640,9 +770,9 @@ 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) @@ -667,6 +797,11 @@ 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); @@ -739,6 +874,16 @@ 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 = (void *)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), @@ -746,6 +891,7 @@ 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, }, }; 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