[PATCH v4 2/2] mmc: sdhci-of-aspeed: Handle optional controller reset
From: Ryan Chen <ryan_chen@aspeedtech.com>
Date: 2026-03-24 01:58:57
Also in:
linux-aspeed, linux-devicetree, linux-mmc, lkml, openbmc
Subsystem:
aspeed sd/mmc driver, multimedia card (mmc), secure digital (sd) and sdio subsystem, secure digital host controller interface (sdhci) driver, the rest · Maintainers:
Andrew Jeffery, Ulf Hansson, Adrian Hunter, Linus Torvalds
Get the optional reset line for the ASPEED SD controller during probe by using devm_reset_control_get_optional_exclusive_deasserted(). This allows platforms such as AST2700, which require the SD controller to be taken out of reset before use, to work with the existing driver. Acked-by: Adrian Hunter <adrian.hunter@intel.com> Signed-off-by: Ryan Chen <ryan_chen@aspeedtech.com> --- Changes in v4: - rebase git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc.git next branch fix the conflit. Changes in v2: - use devm_reset_control_get_optional_exclusive_deasserted replace reset_control_get_optional_exclusive. - add include reset.h --- drivers/mmc/host/sdhci-of-aspeed.c | 6 ++++++ 1 file changed, 6 insertions(+)
diff --git a/drivers/mmc/host/sdhci-of-aspeed.c b/drivers/mmc/host/sdhci-of-aspeed.c
index 4296def69436..f5d973783cbe 100644
--- a/drivers/mmc/host/sdhci-of-aspeed.c
+++ b/drivers/mmc/host/sdhci-of-aspeed.c@@ -13,6 +13,7 @@ #include <linux/of.h> #include <linux/of_platform.h> #include <linux/platform_device.h> +#include <linux/reset.h> #include <linux/spinlock.h> #include "sdhci-pltfm.h"
@@ -519,6 +520,7 @@ static struct platform_driver aspeed_sdhci_driver = { static int aspeed_sdc_probe(struct platform_device *pdev) { + struct reset_control *reset; struct device_node *parent; struct aspeed_sdc *sdc; int ret;
@@ -529,6 +531,10 @@ static int aspeed_sdc_probe(struct platform_device *pdev) spin_lock_init(&sdc->lock); + reset = devm_reset_control_get_optional_exclusive_deasserted(&pdev->dev, NULL); + if (IS_ERR(reset)) + return dev_err_probe(&pdev->dev, PTR_ERR(reset), "unable to acquire reset\n"); + sdc->clk = devm_clk_get(&pdev->dev, NULL); if (IS_ERR(sdc->clk)) return PTR_ERR(sdc->clk);
--
2.34.1