mmc: sdhci-tegra: Add Device Tree probing support

Add hooks to read gpio configuration out of the device tree node.

[grant.likely: Rewrite of original patch from John Bonesio]
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
[swarren: Fixed tegra_sdhci_get_ro() to retrieve pdata correctly]
[swarren: Reworked to avoid #ifdef CONFIG_OF]
[swarren: Reworked binding based on fsl-imx-esdhc.txt]
[swarren: Documented binding]
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Chris Ball <cjb@laptop.org>

1 files changed, 40 insertions, 11 deletions

diff --git a/drivers/mmc/host/sdhci-tegra.c b/drivers/mmc/host/sdhci-tegra.c
index 18b0bd31de78..8a114b6211c7 100644
--- a/drivers/mmc/host/sdhci-tegra.c
+++ b/drivers/mmc/host/sdhci-tegra.c
@@ -17,6 +17,7 @@
 #include <linux/platform_device.h>
 #include <linux/clk.h>
 #include <linux/io.h>
+#include <linux/of_gpio.h>
 #include <linux/gpio.h>
 #include <linux/mmc/card.h>
 #include <linux/mmc/host.h>
@@ -73,10 +74,8 @@ static void tegra_sdhci_writel(struct sdhci_host *host, u32 val, int reg)
 
 static unsigned int tegra_sdhci_get_ro(struct sdhci_host *sdhci)
 {
-        struct platform_device *pdev = to_platform_device(mmc_dev(sdhci->mmc));
-        struct tegra_sdhci_platform_data *plat;
-
-        plat = pdev->dev.platform_data;
+        struct sdhci_pltfm_host *pltfm_host = sdhci_priv(sdhci);
+        struct tegra_sdhci_platform_data *plat = pltfm_host->priv;
 
         if (!gpio_is_valid(plat->wp_gpio))
                 return -1;
@@ -94,12 +93,10 @@ static irqreturn_t carddetect_irq(int irq, void *data)
 
 static int tegra_sdhci_8bit(struct sdhci_host *host, int bus_width)
 {
-        struct platform_device *pdev = to_platform_device(mmc_dev(host->mmc));
-        struct tegra_sdhci_platform_data *plat;
+        struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+        struct tegra_sdhci_platform_data *plat = pltfm_host->priv;
         u32 ctrl;
 
-        plat = pdev->dev.platform_data;
-
         ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL);
         if (plat->is_8bit && bus_width == MMC_BUS_WIDTH_8) {
                 ctrl &= ~SDHCI_CTRL_4BITBUS;
@@ -131,6 +128,34 @@ static struct sdhci_pltfm_data sdhci_tegra_pdata = {
         .ops  = &tegra_sdhci_ops,
 };
 
+static const struct of_device_id sdhci_tegra_dt_match[] __devinitdata = {
+        { .compatible = "nvidia,tegra20-sdhci", },
+        {}
+};
+MODULE_DEVICE_TABLE(of, sdhci_dt_ids);
+
+static struct tegra_sdhci_platform_data * __devinit sdhci_tegra_dt_parse_pdata(
+                                                struct platform_device *pdev)
+{
+        struct tegra_sdhci_platform_data *plat;
+        struct device_node *np = pdev->dev.of_node;
+
+        if (!np)
+                return NULL;
+
+        plat = devm_kzalloc(&pdev->dev, sizeof(*plat), GFP_KERNEL);
+        if (!plat) {
+                dev_err(&pdev->dev, "Can't allocate platform data\n");
+                return NULL;
+        }
+
+        plat->cd_gpio = of_get_named_gpio(np, "cd-gpios", 0);
+        plat->wp_gpio = of_get_named_gpio(np, "wp-gpios", 0);
+        plat->power_gpio = of_get_named_gpio(np, "power-gpios", 0);
+
+        return plat;
+}
+
 static int __devinit sdhci_tegra_probe(struct platform_device *pdev)
 {
         struct sdhci_pltfm_host *pltfm_host;
@@ -147,12 +172,17 @@ static int __devinit sdhci_tegra_probe(struct platform_device *pdev)
 
         plat = pdev->dev.platform_data;
 
+        if (plat == NULL)
+                plat = sdhci_tegra_dt_parse_pdata(pdev);
+
         if (plat == NULL) {
                 dev_err(mmc_dev(host->mmc), "missing platform data\n");
                 rc = -ENXIO;
                 goto err_no_plat;
         }
 
+        pltfm_host->priv = plat;
+
         if (gpio_is_valid(plat->power_gpio)) {
                 rc = gpio_request(plat->power_gpio, "sdhci_power");
                 if (rc) {
@@ -247,13 +277,11 @@ static int __devexit sdhci_tegra_remove(struct platform_device *pdev)
 {
         struct sdhci_host *host = platform_get_drvdata(pdev);
         struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
-        struct tegra_sdhci_platform_data *plat;
+        struct tegra_sdhci_platform_data *plat = pltfm_host->priv;
         int dead = (readl(host->ioaddr + SDHCI_INT_STATUS) == 0xffffffff);
 
         sdhci_remove_host(host, dead);
 
-        plat = pdev->dev.platform_data;
-
         if (gpio_is_valid(plat->wp_gpio)) {
                 tegra_gpio_disable(plat->wp_gpio);
                 gpio_free(plat->wp_gpio);
@@ -282,6 +310,7 @@ static struct platform_driver sdhci_tegra_driver = {
         .driver         = {
                 .name   = "sdhci-tegra",
                 .owner  = THIS_MODULE,
+                .of_match_table = sdhci_tegra_dt_match,
         },
         .probe          = sdhci_tegra_probe,
         .remove         = __devexit_p(sdhci_tegra_remove),