[PATCH V2 23/27] mmc: mmci: add variant property to request a reset
From: Ulf Hansson <hidden>
Date: 2018-10-01 09:31:27
Also in:
linux-devicetree, linux-mmc, lkml
On 21 September 2018 at 11:46, Ludovic Barre [off-list ref] wrote:
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From: Ludovic Barre <redacted> Some variants could require a reset. STM32 sdmmc variant needs to reset hardware block during the power cycle procedure (for re-initialization) Signed-off-by: Ludovic Barre <redacted> --- Documentation/devicetree/bindings/mmc/mmci.txt | 2 ++ drivers/mmc/host/mmci.c | 9 +++++++++ drivers/mmc/host/mmci.h | 4 ++++ 3 files changed, 15 insertions(+)diff --git a/Documentation/devicetree/bindings/mmc/mmci.txt b/Documentation/devicetree/bindings/mmc/mmci.txt index 03796cf..e952707 100644 --- a/Documentation/devicetree/bindings/mmc/mmci.txt +++ b/Documentation/devicetree/bindings/mmc/mmci.txt@@ -11,6 +11,8 @@ Required properties: - compatible : contains "arm,pl18x", "arm,primecell". - vmmc-supply : phandle to the regulator device tree node, mentioned as the VCC/VDD supply in the eMMC/SD specs. +depend of variant: +- resets : phandle to internal reset line.
This looks like a thing depending on the SoC, rather than on the variant. Therefore, I suggest you move this to be an optional DT property. Also, please move the DT doc update into a separate patch.
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Optional properties: - arm,primecell-periphid : contains the PrimeCell Peripheral ID, it overridesdiff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c index b1d5bc5..6b3c33f 100644 --- a/drivers/mmc/host/mmci.c +++ b/drivers/mmc/host/mmci.c@@ -37,6 +37,7 @@ #include <linux/pm_runtime.h> #include <linux/types.h> #include <linux/pinctrl/consumer.h> +#include <linux/reset.h> #include <asm/div64.h> #include <asm/io.h>@@ -1854,6 +1855,14 @@ static int mmci_probe(struct amba_device *dev, dev_dbg(mmc_dev(mmc), "clocking block at %u Hz\n", mmc->f_max); + if (variant->reset) { + host->rst = devm_reset_control_get_exclusive(&dev->dev, NULL);
As suggested, let's make this optional and not depending on the variant.
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+ if (IS_ERR(host->rst)) { + ret = PTR_ERR(host->rst); + goto clk_disable; + } + } + /* Get regulators and the supported OCR mask */ ret = mmc_regulator_get_supply(mmc); if (ret)diff --git a/drivers/mmc/host/mmci.h b/drivers/mmc/host/mmci.h index e130689..f0fa185 100644 --- a/drivers/mmc/host/mmci.h +++ b/drivers/mmc/host/mmci.h@@ -247,6 +247,7 @@ struct mmci_host; * @start_err: bitmask identifying the STARTBITERR bit inside MMCISTATUS * register. * @opendrain: bitmask identifying the OPENDRAIN bit inside MMCIPOWER register + * @reset: true if variant has need reset signal. */ struct variant_data { unsigned int clkreg;@@ -285,6 +286,7 @@ struct variant_data { bool qcom_dml; bool reversed_irq_handling; bool mmcimask1; + bool reset; unsigned int irq_pio_mask; u32 start_err; u32 opendrain;@@ -318,6 +320,8 @@ struct mmci_host { struct clk *clk; bool singleirq; + struct reset_control *rst; + spinlock_t lock; unsigned int mclk; --2.7.4
Kind regards Uffe