Add voltage switching infrastructure for UHS-I modes by integrating both
regulator framework (for supply voltage control) and pinctrl state
switching (for pin drive strength optimization).
- Add regulator supply parsing and voltage switching callback
- Add optional pinctrl state switching between "default" (3.3V) and
"state_uhs" (1.8V) configurations
- Enable coordinated voltage and pin configuration changes for UHS modes
This provides complete voltage switching support while maintaining
backward compatibility when pinctrl states are not defined.
Signed-off-by: Iker Pedrosa <ikerpedrosam@gmail.com>
---
drivers/mmc/host/sdhci-of-k1.c | 59 ++++++++++++++++++++++++++++++++++++++++++
1 file changed, 59 insertions(+)
diff --git a/drivers/mmc/host/sdhci-of-k1.c b/drivers/mmc/host/sdhci-of-k1.c
index 585c7eca6ebf253aac466dd37cef029deb63f692..8af117a8e271c04a80d8dc7bb5ce12075652dd7a 100644
--- a/drivers/mmc/host/sdhci-of-k1.c
+++ b/drivers/mmc/host/sdhci-of-k1.c
@@ -15,6 +15,7 @@
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
+#include <linux/pinctrl/consumer.h>
#include <linux/platform_device.h>
#include "sdhci.h"
@@ -70,6 +71,9 @@
struct spacemit_sdhci_host {
struct clk *clk_core;
struct clk *clk_io;
+ struct pinctrl *pinctrl;
+ struct pinctrl_state *pinctrl_default;
+ struct pinctrl_state *pinctrl_uhs;
};
/* All helper functions will update clr/set while preserve rest bits */
@@ -218,6 +222,42 @@ static void spacemit_sdhci_pre_hs400_to_hs200(struct mmc_host *mmc)
SPACEMIT_SDHC_PHY_CTRL_REG);
}
+static void spacemit_sdhci_voltage_switch(struct sdhci_host *host)
+{
+ struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+ struct spacemit_sdhci_host *sdhst = sdhci_pltfm_priv(pltfm_host);
+ struct mmc_ios *ios = &host->mmc->ios;
+ struct pinctrl_state *state;
+ int ret;
+
+ /* Select appropriate pinctrl state based on signal voltage */
+ if (sdhst->pinctrl) {
+ switch (ios->signal_voltage) {
+ case MMC_SIGNAL_VOLTAGE_330:
+ state = sdhst->pinctrl_default;
+ break;
+ case MMC_SIGNAL_VOLTAGE_180:
+ state = sdhst->pinctrl_uhs;
+ break;
+ default:
+ dev_warn(mmc_dev(host->mmc), "unsupported voltage %d\n",
+ ios->signal_voltage);
+ return;
+ }
+
+ if (state) {
+ ret = pinctrl_select_state(sdhst->pinctrl, state);
+ if (ret) {
+ dev_warn(mmc_dev(host->mmc),
+ "failed to select pinctrl state: %d\n", ret);
+ return;
+ }
+ dev_dbg(mmc_dev(host->mmc), "switched to %s pinctrl state\n",
+ ios->signal_voltage == MMC_SIGNAL_VOLTAGE_180 ? "UHS" : "default");
+ }
+ }
+}
+
static inline int spacemit_sdhci_get_clocks(struct device *dev,
struct sdhci_pltfm_host *pltfm_host)
{
@@ -242,6 +282,7 @@ static const struct sdhci_ops spacemit_sdhci_ops = {
.set_bus_width = sdhci_set_bus_width,
.set_clock = spacemit_sdhci_set_clock,
.set_uhs_signaling = spacemit_sdhci_set_uhs_signaling,
+ .voltage_switch = spacemit_sdhci_voltage_switch,
};
static const struct sdhci_pltfm_data spacemit_sdhci_k1_pdata = {
@@ -293,6 +334,24 @@ static int spacemit_sdhci_probe(struct platform_device *pdev)
host->mmc->caps |= MMC_CAP_NEED_RSP_BUSY;
+ sdhst = sdhci_pltfm_priv(pltfm_host);
+ sdhst->pinctrl = devm_pinctrl_get(dev);
+ if (!IS_ERR(sdhst->pinctrl)) {
+ sdhst->pinctrl_default = pinctrl_lookup_state(sdhst->pinctrl, "default");
+ if (IS_ERR(sdhst->pinctrl_default))
+ sdhst->pinctrl_default = NULL;
+
+ sdhst->pinctrl_uhs = pinctrl_lookup_state(sdhst->pinctrl, "state_uhs");
+ if (IS_ERR(sdhst->pinctrl_uhs))
+ sdhst->pinctrl_uhs = NULL;
+
+ dev_dbg(dev, "pinctrl setup: default=%p, uhs=%p\n",
+ sdhst->pinctrl_default, sdhst->pinctrl_uhs);
+ } else {
+ sdhst->pinctrl = NULL;
+ dev_dbg(dev, "pinctrl not available, voltage switching will work without it\n");
+ }
+
ret = spacemit_sdhci_get_clocks(dev, pltfm_host);
if (ret)
goto err_pltfm;
--
2.53.0On 09/03/2026 13:40, Iker Pedrosa wrote:
> Add voltage switching infrastructure for UHS-I modes by integrating both
> regulator framework (for supply voltage control) and pinctrl state
> switching (for pin drive strength optimization).
>
> - Add regulator supply parsing and voltage switching callback
> - Add optional pinctrl state switching between "default" (3.3V) and
> "state_uhs" (1.8V) configurations
> - Enable coordinated voltage and pin configuration changes for UHS modes
>
> This provides complete voltage switching support while maintaining
> backward compatibility when pinctrl states are not defined.
>
> Signed-off-by: Iker Pedrosa <ikerpedrosam@gmail.com>
> ---
> drivers/mmc/host/sdhci-of-k1.c | 59 ++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 59 insertions(+)
>
> diff --git a/drivers/mmc/host/sdhci-of-k1.c b/drivers/mmc/host/sdhci-of-k1.c
> index 585c7eca6ebf253aac466dd37cef029deb63f692..8af117a8e271c04a80d8dc7bb5ce12075652dd7a 100644
> --- a/drivers/mmc/host/sdhci-of-k1.c
> +++ b/drivers/mmc/host/sdhci-of-k1.c
> @@ -15,6 +15,7 @@
> #include <linux/module.h>
> #include <linux/of.h>
> #include <linux/of_device.h>
> +#include <linux/pinctrl/consumer.h>
Conflicts with "mmc: sdhci-of-k1: add reset support"
Ensure patch applies to 'next' branch of
git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc.git
> #include <linux/platform_device.h>
>
> #include "sdhci.h"
> @@ -70,6 +71,9 @@
> struct spacemit_sdhci_host {
> struct clk *clk_core;
> struct clk *clk_io;
> + struct pinctrl *pinctrl;
> + struct pinctrl_state *pinctrl_default;
> + struct pinctrl_state *pinctrl_uhs;
> };
>
> /* All helper functions will update clr/set while preserve rest bits */
> @@ -218,6 +222,42 @@ static void spacemit_sdhci_pre_hs400_to_hs200(struct mmc_host *mmc)
> SPACEMIT_SDHC_PHY_CTRL_REG);
> }
>
> +static void spacemit_sdhci_voltage_switch(struct sdhci_host *host)
> +{
> + struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
> + struct spacemit_sdhci_host *sdhst = sdhci_pltfm_priv(pltfm_host);
> + struct mmc_ios *ios = &host->mmc->ios;
> + struct pinctrl_state *state;
> + int ret;
> +
> + /* Select appropriate pinctrl state based on signal voltage */
> + if (sdhst->pinctrl) {
> + switch (ios->signal_voltage) {
->voltage_switch() is called only for ios->signal_voltage == MMC_SIGNAL_VOLTAGE_180
> + case MMC_SIGNAL_VOLTAGE_330:
> + state = sdhst->pinctrl_default;
> + break;
> + case MMC_SIGNAL_VOLTAGE_180:
> + state = sdhst->pinctrl_uhs;
> + break;
> + default:
> + dev_warn(mmc_dev(host->mmc), "unsupported voltage %d\n",
> + ios->signal_voltage);
> + return;
> + }
> +
> + if (state) {
> + ret = pinctrl_select_state(sdhst->pinctrl, state);
> + if (ret) {
> + dev_warn(mmc_dev(host->mmc),
> + "failed to select pinctrl state: %d\n", ret);
> + return;
> + }
> + dev_dbg(mmc_dev(host->mmc), "switched to %s pinctrl state\n",
> + ios->signal_voltage == MMC_SIGNAL_VOLTAGE_180 ? "UHS" : "default");
> + }
> + }
> +}
> +
> static inline int spacemit_sdhci_get_clocks(struct device *dev,
> struct sdhci_pltfm_host *pltfm_host)
> {
> @@ -242,6 +282,7 @@ static const struct sdhci_ops spacemit_sdhci_ops = {
> .set_bus_width = sdhci_set_bus_width,
> .set_clock = spacemit_sdhci_set_clock,
> .set_uhs_signaling = spacemit_sdhci_set_uhs_signaling,
> + .voltage_switch = spacemit_sdhci_voltage_switch,
> };
>
> static const struct sdhci_pltfm_data spacemit_sdhci_k1_pdata = {
> @@ -293,6 +334,24 @@ static int spacemit_sdhci_probe(struct platform_device *pdev)
>
> host->mmc->caps |= MMC_CAP_NEED_RSP_BUSY;
>
> + sdhst = sdhci_pltfm_priv(pltfm_host);
> + sdhst->pinctrl = devm_pinctrl_get(dev);
> + if (!IS_ERR(sdhst->pinctrl)) {
> + sdhst->pinctrl_default = pinctrl_lookup_state(sdhst->pinctrl, "default");
> + if (IS_ERR(sdhst->pinctrl_default))
> + sdhst->pinctrl_default = NULL;
> +
> + sdhst->pinctrl_uhs = pinctrl_lookup_state(sdhst->pinctrl, "state_uhs");
> + if (IS_ERR(sdhst->pinctrl_uhs))
> + sdhst->pinctrl_uhs = NULL;
> +
> + dev_dbg(dev, "pinctrl setup: default=%p, uhs=%p\n",
> + sdhst->pinctrl_default, sdhst->pinctrl_uhs);
> + } else {
> + sdhst->pinctrl = NULL;
> + dev_dbg(dev, "pinctrl not available, voltage switching will work without it\n");
> + }
> +
> ret = spacemit_sdhci_get_clocks(dev, pltfm_host);
> if (ret)
> goto err_pltfm;
>
Hi Iker,
On 12:40 Mon 09 Mar , Iker Pedrosa wrote:
> Add voltage switching infrastructure for UHS-I modes by integrating both
> regulator framework (for supply voltage control) and pinctrl state
> switching (for pin drive strength optimization).
>
> - Add regulator supply parsing and voltage switching callback
> - Add optional pinctrl state switching between "default" (3.3V) and
> "state_uhs" (1.8V) configurations
> - Enable coordinated voltage and pin configuration changes for UHS modes
>
> This provides complete voltage switching support while maintaining
> backward compatibility when pinctrl states are not defined.
>
> Signed-off-by: Iker Pedrosa <ikerpedrosam@gmail.com>
> ---
> drivers/mmc/host/sdhci-of-k1.c | 59 ++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 59 insertions(+)
>
> diff --git a/drivers/mmc/host/sdhci-of-k1.c b/drivers/mmc/host/sdhci-of-k1.c
> index 585c7eca6ebf253aac466dd37cef029deb63f692..8af117a8e271c04a80d8dc7bb5ce12075652dd7a 100644
> --- a/drivers/mmc/host/sdhci-of-k1.c
> +++ b/drivers/mmc/host/sdhci-of-k1.c
> @@ -15,6 +15,7 @@
> #include <linux/module.h>
> #include <linux/of.h>
> #include <linux/of_device.h>
> +#include <linux/pinctrl/consumer.h>
> #include <linux/platform_device.h>
>
> #include "sdhci.h"
> @@ -70,6 +71,9 @@
> struct spacemit_sdhci_host {
> struct clk *clk_core;
> struct clk *clk_io;
> + struct pinctrl *pinctrl;
> + struct pinctrl_state *pinctrl_default;
> + struct pinctrl_state *pinctrl_uhs;
> };
>
> /* All helper functions will update clr/set while preserve rest bits */
> @@ -218,6 +222,42 @@ static void spacemit_sdhci_pre_hs400_to_hs200(struct mmc_host *mmc)
> SPACEMIT_SDHC_PHY_CTRL_REG);
> }
>
> +static void spacemit_sdhci_voltage_switch(struct sdhci_host *host)
> +{
> + struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
> + struct spacemit_sdhci_host *sdhst = sdhci_pltfm_priv(pltfm_host);
> + struct mmc_ios *ios = &host->mmc->ios;
> + struct pinctrl_state *state;
> + int ret;
> +
> + /* Select appropriate pinctrl state based on signal voltage */
> + if (sdhst->pinctrl) {
do a sanity check, then abort it early, the advantage is that you can get rid of
one indetation for next code..
if (!sdhst->pinctrl)
return;
> + switch (ios->signal_voltage) {
> + case MMC_SIGNAL_VOLTAGE_330:
> + state = sdhst->pinctrl_default;
> + break;
> + case MMC_SIGNAL_VOLTAGE_180:
> + state = sdhst->pinctrl_uhs;
> + break;
> + default:
> + dev_warn(mmc_dev(host->mmc), "unsupported voltage %d\n",
> + ios->signal_voltage);
> + return;
> + }
> +
> + if (state) {
> + ret = pinctrl_select_state(sdhst->pinctrl, state);
> + if (ret) {
> + dev_warn(mmc_dev(host->mmc),
> + "failed to select pinctrl state: %d\n", ret);
> + return;
> + }
> + dev_dbg(mmc_dev(host->mmc), "switched to %s pinctrl state\n",
> + ios->signal_voltage == MMC_SIGNAL_VOLTAGE_180 ? "UHS" : "default");
> + }
> + }
> +}
> +
> static inline int spacemit_sdhci_get_clocks(struct device *dev,
> struct sdhci_pltfm_host *pltfm_host)
> {
> @@ -242,6 +282,7 @@ static const struct sdhci_ops spacemit_sdhci_ops = {
> .set_bus_width = sdhci_set_bus_width,
> .set_clock = spacemit_sdhci_set_clock,
> .set_uhs_signaling = spacemit_sdhci_set_uhs_signaling,
> + .voltage_switch = spacemit_sdhci_voltage_switch,
> };
>
> static const struct sdhci_pltfm_data spacemit_sdhci_k1_pdata = {
> @@ -293,6 +334,24 @@ static int spacemit_sdhci_probe(struct platform_device *pdev)
>
> host->mmc->caps |= MMC_CAP_NEED_RSP_BUSY;
>
> + sdhst = sdhci_pltfm_priv(pltfm_host);
..
> + sdhst->pinctrl = devm_pinctrl_get(dev);
> + if (!IS_ERR(sdhst->pinctrl)) {
> + sdhst->pinctrl_default = pinctrl_lookup_state(sdhst->pinctrl, "default");
> + if (IS_ERR(sdhst->pinctrl_default))
> + sdhst->pinctrl_default = NULL;
> +
> + sdhst->pinctrl_uhs = pinctrl_lookup_state(sdhst->pinctrl, "state_uhs");
> + if (IS_ERR(sdhst->pinctrl_uhs))
> + sdhst->pinctrl_uhs = NULL;
> +
> + dev_dbg(dev, "pinctrl setup: default=%p, uhs=%p\n",
> + sdhst->pinctrl_default, sdhst->pinctrl_uhs);
> + } else {
> + sdhst->pinctrl = NULL;
> + dev_dbg(dev, "pinctrl not available, voltage switching will work without it\n");
> + }
> +
how about creating a function spacemit_sdhci_get_pins()? similar as get
resource for clock, will more readable.
> ret = spacemit_sdhci_get_clocks(dev, pltfm_host);
> if (ret)
> goto err_pltfm;
>
> --
> 2.53.0
>
--
Yixun Lan (dlan)
El lun, 9 mar 2026 a las 14:22, Yixun Lan (<dlan@kernel.org>) escribió:
>
> Hi Iker,
>
> On 12:40 Mon 09 Mar , Iker Pedrosa wrote:
> > Add voltage switching infrastructure for UHS-I modes by integrating both
> > regulator framework (for supply voltage control) and pinctrl state
> > switching (for pin drive strength optimization).
> >
> > - Add regulator supply parsing and voltage switching callback
> > - Add optional pinctrl state switching between "default" (3.3V) and
> > "state_uhs" (1.8V) configurations
> > - Enable coordinated voltage and pin configuration changes for UHS modes
> >
> > This provides complete voltage switching support while maintaining
> > backward compatibility when pinctrl states are not defined.
> >
> > Signed-off-by: Iker Pedrosa <ikerpedrosam@gmail.com>
> > ---
> > drivers/mmc/host/sdhci-of-k1.c | 59 ++++++++++++++++++++++++++++++++++++++++++
> > 1 file changed, 59 insertions(+)
> >
> > diff --git a/drivers/mmc/host/sdhci-of-k1.c b/drivers/mmc/host/sdhci-of-k1.c
> > index 585c7eca6ebf253aac466dd37cef029deb63f692..8af117a8e271c04a80d8dc7bb5ce12075652dd7a 100644
> > --- a/drivers/mmc/host/sdhci-of-k1.c
> > +++ b/drivers/mmc/host/sdhci-of-k1.c
> > @@ -15,6 +15,7 @@
> > #include <linux/module.h>
> > #include <linux/of.h>
> > #include <linux/of_device.h>
> > +#include <linux/pinctrl/consumer.h>
> > #include <linux/platform_device.h>
> >
> > #include "sdhci.h"
> > @@ -70,6 +71,9 @@
> > struct spacemit_sdhci_host {
> > struct clk *clk_core;
> > struct clk *clk_io;
> > + struct pinctrl *pinctrl;
> > + struct pinctrl_state *pinctrl_default;
> > + struct pinctrl_state *pinctrl_uhs;
> > };
> >
> > /* All helper functions will update clr/set while preserve rest bits */
> > @@ -218,6 +222,42 @@ static void spacemit_sdhci_pre_hs400_to_hs200(struct mmc_host *mmc)
> > SPACEMIT_SDHC_PHY_CTRL_REG);
> > }
> >
> > +static void spacemit_sdhci_voltage_switch(struct sdhci_host *host)
> > +{
> > + struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
> > + struct spacemit_sdhci_host *sdhst = sdhci_pltfm_priv(pltfm_host);
> > + struct mmc_ios *ios = &host->mmc->ios;
> > + struct pinctrl_state *state;
> > + int ret;
> > +
> > + /* Select appropriate pinctrl state based on signal voltage */
> > + if (sdhst->pinctrl) {
> do a sanity check, then abort it early, the advantage is that you can get rid of
> one indetation for next code..
>
> if (!sdhst->pinctrl)
> return;
>
Makes sense. I'll get it ready for the next version.
>
> > + switch (ios->signal_voltage) {
> > + case MMC_SIGNAL_VOLTAGE_330:
> > + state = sdhst->pinctrl_default;
> > + break;
> > + case MMC_SIGNAL_VOLTAGE_180:
> > + state = sdhst->pinctrl_uhs;
> > + break;
> > + default:
> > + dev_warn(mmc_dev(host->mmc), "unsupported voltage %d\n",
> > + ios->signal_voltage);
> > + return;
> > + }
> > +
> > + if (state) {
> > + ret = pinctrl_select_state(sdhst->pinctrl, state);
> > + if (ret) {
> > + dev_warn(mmc_dev(host->mmc),
> > + "failed to select pinctrl state: %d\n", ret);
> > + return;
> > + }
> > + dev_dbg(mmc_dev(host->mmc), "switched to %s pinctrl state\n",
> > + ios->signal_voltage == MMC_SIGNAL_VOLTAGE_180 ? "UHS" : "default");
> > + }
> > + }
> > +}
> > +
> > static inline int spacemit_sdhci_get_clocks(struct device *dev,
> > struct sdhci_pltfm_host *pltfm_host)
> > {
> > @@ -242,6 +282,7 @@ static const struct sdhci_ops spacemit_sdhci_ops = {
> > .set_bus_width = sdhci_set_bus_width,
> > .set_clock = spacemit_sdhci_set_clock,
> > .set_uhs_signaling = spacemit_sdhci_set_uhs_signaling,
> > + .voltage_switch = spacemit_sdhci_voltage_switch,
> > };
> >
> > static const struct sdhci_pltfm_data spacemit_sdhci_k1_pdata = {
> > @@ -293,6 +334,24 @@ static int spacemit_sdhci_probe(struct platform_device *pdev)
> >
> > host->mmc->caps |= MMC_CAP_NEED_RSP_BUSY;
> >
> > + sdhst = sdhci_pltfm_priv(pltfm_host);
> ..
> > + sdhst->pinctrl = devm_pinctrl_get(dev);
> > + if (!IS_ERR(sdhst->pinctrl)) {
> > + sdhst->pinctrl_default = pinctrl_lookup_state(sdhst->pinctrl, "default");
> > + if (IS_ERR(sdhst->pinctrl_default))
> > + sdhst->pinctrl_default = NULL;
> > +
> > + sdhst->pinctrl_uhs = pinctrl_lookup_state(sdhst->pinctrl, "state_uhs");
> > + if (IS_ERR(sdhst->pinctrl_uhs))
> > + sdhst->pinctrl_uhs = NULL;
> > +
> > + dev_dbg(dev, "pinctrl setup: default=%p, uhs=%p\n",
> > + sdhst->pinctrl_default, sdhst->pinctrl_uhs);
> > + } else {
> > + sdhst->pinctrl = NULL;
> > + dev_dbg(dev, "pinctrl not available, voltage switching will work without it\n");
> > + }
> > +
> how about creating a function spacemit_sdhci_get_pins()? similar as get
> resource for clock, will more readable.
Yes, I'll do that. Thank you for the feedback.
>
> > ret = spacemit_sdhci_get_clocks(dev, pltfm_host);
> > if (ret)
> > goto err_pltfm;
> >
> > --
> > 2.53.0
> >
>
> --
> Yixun Lan (dlan)
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