mmc: mxs-mmc: copy wp_gpio in struct mxs_mmc_host

Copy wp_gpio from platform_data into struct mxs_mmc_host, so that
the use of platform_data can be limited in probe function, which
will ease the device tree probe.
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Marek Vasut <marex@denx.de>
Acked-by: Chris Ball <cjb@laptop.org>

drivers/mmc/host/mxs-mmc.c

@@ -160,21 +160,17 @@ struct mxs_mmc_host {
 	unsigned char			bus_width;
 	spinlock_t			lock;
 	int				sdio_irq_en;
+	int				wp_gpio;
 };
 
 static int mxs_mmc_get_ro(struct mmc_host *mmc)
 {
 	struct mxs_mmc_host *host = mmc_priv(mmc);
-	struct mxs_mmc_platform_data *pdata =
-		mmc_dev(host->mmc)->platform_data;
 
-	if (!pdata)
-		return -EFAULT;
-
-	if (!gpio_is_valid(pdata->wp_gpio))
+	if (!gpio_is_valid(host->wp_gpio))
 		return -EINVAL;
 
-	return gpio_get_value(pdata->wp_gpio);
+	return gpio_get_value(host->wp_gpio);
 }
 
 static int mxs_mmc_get_cd(struct mmc_host *mmc)
@@ -758,6 +754,7 @@ static int mxs_mmc_probe(struct platform_device *pdev)
 			mmc->caps |= MMC_CAP_4_BIT_DATA | MMC_CAP_8_BIT_DATA;
 		if (pdata->flags & SLOTF_4_BIT_CAPABLE)
 			mmc->caps |= MMC_CAP_4_BIT_DATA;
+		host->wp_gpio = pdata->wp_gpio;
 	}
 
 	mmc->f_min = 400000;