From: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
Implement voltage switch, supporting modes up to SDR-50.
Based on work by Shinobu Uehara, Rob Taylor, William Towle and Ian Molton.
Signed-off-by: Ben Hutchings <ben.hutchings@xxxxxxxxxxxxxxx>
Signed-off-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
---
Changes since RFC:
* added binding docs
* use mmc_regulator_set_vqmmc instead of open coding it
* rename DT binding name and pinctrl variables to "*uhs" instead of "*1v8"
Documentation/devicetree/bindings/mmc/tmio_mmc.txt | 3 ++
drivers/mmc/host/sh_mobile_sdhi.c | 49 ++++++++++++++++++++++
2 files changed, 52 insertions(+)
diff --git a/Documentation/devicetree/bindings/mmc/tmio_mmc.txt b/Documentation/devicetree/bindings/mmc/tmio_mmc.txt
index 7fb746dd1a68ca..0f610d4b5b005f 100644
--- a/Documentation/devicetree/bindings/mmc/tmio_mmc.txt
+++ b/Documentation/devicetree/bindings/mmc/tmio_mmc.txt
@@ -26,3 +26,6 @@ Required properties:
Optional properties:
- toshiba,mmc-wrprotect-disable: write-protect detection is unavailable
+- pinctrl-names: should be "default", "state_uhs"
+- pinctrl-0: should contain default/high speed pin ctrl
+- pinctrl-1: should contain uhs mode pin ctrl
diff --git a/drivers/mmc/host/sh_mobile_sdhi.c b/drivers/mmc/host/sh_mobile_sdhi.c
index 8fd1d6b29190b6..5d2a852f17eebd 100644
--- a/drivers/mmc/host/sh_mobile_sdhi.c
+++ b/drivers/mmc/host/sh_mobile_sdhi.c
@@ -32,6 +32,9 @@
#include <linux/mfd/tmio.h>
#include <linux/sh_dma.h>
#include <linux/delay.h>
+#include <linux/pinctrl/consumer.h>
+#include <linux/pinctrl/pinctrl-state.h>
+#include <linux/regulator/consumer.h>
#include "tmio_mmc.h"
@@ -97,6 +100,8 @@ struct sh_mobile_sdhi {
struct clk *clk;
struct tmio_mmc_data mmc_data;
struct tmio_mmc_dma dma_priv;
+ struct pinctrl *pinctrl;
+ struct pinctrl_state *pins_default, *pins_uhs;
};
static void sh_mobile_sdhi_sdbuf_width(struct tmio_mmc_host *host, int width)
@@ -205,6 +210,43 @@ static void sh_mobile_sdhi_clk_disable(struct tmio_mmc_host *host)
clk_disable_unprepare(priv->clk);
}
+static int sh_mobile_sdhi_start_signal_voltage_switch(struct tmio_mmc_host *host,
+ struct mmc_ios *ios)
+{
+ struct sh_mobile_sdhi *priv = host_to_priv(host);
+ struct pinctrl_state *pin_state;
+ int ret;
+
+ switch (ios->signal_voltage) {
+ case MMC_SIGNAL_VOLTAGE_330:
+ pin_state = priv->pins_default;
+ break;
+ case MMC_SIGNAL_VOLTAGE_180:
+ pin_state = priv->pins_uhs;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ /*
+ * If anything is missing, assume signal voltage is fixed at
+ * 3.3V and succeed/fail accordingly.
+ */
+ if (IS_ERR(priv->pinctrl) || IS_ERR(pin_state))
+ return ios->signal_voltage == MMC_SIGNAL_VOLTAGE_330 ? 0 : -EINVAL;
+
+ ret = mmc_regulator_set_vqmmc(host->mmc, ios);
+ if (ret)
+ return ret;
+
+ ret = pinctrl_select_state(priv->pinctrl, pin_state);
+ if (ret)
+ return ret;
+
+ usleep_range(5000, 5500);
+ return 0;
+}
+
static int sh_mobile_sdhi_wait_idle(struct tmio_mmc_host *host)
{
int timeout = 1000;
@@ -296,6 +338,12 @@ static int sh_mobile_sdhi_probe(struct platform_device *pdev)
goto eprobe;
}
+ priv->pinctrl = devm_pinctrl_get(&pdev->dev);
+ if (!IS_ERR(priv->pinctrl)) {
+ priv->pins_default = pinctrl_lookup_state(priv->pinctrl, PINCTRL_STATE_DEFAULT);
+ priv->pins_uhs = pinctrl_lookup_state(priv->pinctrl, "state_uhs");
+ }
+
host = tmio_mmc_host_alloc(pdev);
if (!host) {
ret = -ENOMEM;
@@ -319,6 +367,7 @@ static int sh_mobile_sdhi_probe(struct platform_device *pdev)
host->clk_update = sh_mobile_sdhi_clk_update;
host->clk_disable = sh_mobile_sdhi_clk_disable;
host->multi_io_quirk = sh_mobile_sdhi_multi_io_quirk;
+ host->start_signal_voltage_switch = sh_mobile_sdhi_start_signal_voltage_switch;
/* Orginally registers were 16 bit apart, could be 32 or 64 nowadays */
if (!host->bus_shift && resource_size(res) > 0x100) /* old way to determine the shift */
--
2.7.0
