mmc: omap_hsmmc: support deferred probing for GPIOs

If the CD/WP-GPIOs are not provided by the SoC's GPIO controller,
we need to handle the case where omap_hsmmc is probed earlier than
the GPIO controller chosen in the device tree.

Fix this by checking the return value of of_get_named_gpio against
-EPROBE_DEFER and passing it through to the probe function.

Signed-off-by: Jan Luebbe <jlu@pengutronix.de>
Acked-by: Balaji T K <balajitk@ti.com>
Signed-off-by: Chris Ball <cjb@laptop.org>

diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c
index bc58078..6e44025 100644 (file)
--- a/drivers/mmc/host/omap_hsmmc.c
+++ b/drivers/mmc/host/omap_hsmmc.c
@@ -1717,6 +1717,12 @@ static struct omap_mmc_platform_data *of_get_hsmmc_pdata(struct device *dev)
        struct omap_mmc_platform_data *pdata;
        struct device_node *np = dev->of_node;
        u32 bus_width, max_freq;
+       int cd_gpio, wp_gpio;
+
+       cd_gpio = of_get_named_gpio(np, "cd-gpios", 0);
+       wp_gpio = of_get_named_gpio(np, "wp-gpios", 0);
+       if (cd_gpio == -EPROBE_DEFER || wp_gpio == -EPROBE_DEFER)
+               return ERR_PTR(-EPROBE_DEFER);
 
        pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
        if (!pdata)
@@ -1727,8 +1733,8 @@ static struct omap_mmc_platform_data *of_get_hsmmc_pdata(struct device *dev)
 
        /* This driver only supports 1 slot */
        pdata->nr_slots = 1;
-       pdata->slots[0].switch_pin = of_get_named_gpio(np, "cd-gpios", 0);
-       pdata->slots[0].gpio_wp = of_get_named_gpio(np, "wp-gpios", 0);
+       pdata->slots[0].switch_pin = cd_gpio;
+       pdata->slots[0].gpio_wp = wp_gpio;
 
        if (of_find_property(np, "ti,non-removable", NULL)) {
                pdata->slots[0].nonremovable = true;
@@ -1774,6 +1780,10 @@ static int omap_hsmmc_probe(struct platform_device *pdev)
        match = of_match_device(of_match_ptr(omap_mmc_of_match), &pdev->dev);
        if (match) {
                pdata = of_get_hsmmc_pdata(&pdev->dev);
+
+               if (IS_ERR(pdata))
+                       return PTR_ERR(pdata);
+
                if (match->data) {
                        const u16 *offsetp = match->data;
                        pdata->reg_offset = *offsetp;