[PATCH V10 11/23] mmc: sdhci-uhs2: add set_power() to support vdd2

From: Victor Shih
Date: Fri Aug 18 2023 - 06:05:57 EST

From: Victor Shih <victor.shih@xxxxxxxxxxxxxxxxxxx>

This is a UHS-II version of sdhci's set_power operation.
VDD2, as well as VDD, is handled here.

Signed-off-by: Ben Chuang <ben.chuang@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: AKASHI Takahiro <takahiro.akashi@xxxxxxxxxx>
Signed-off-by: Victor Shih <victor.shih@xxxxxxxxxxxxxxxxxxx>
---

Updates in V10:
- Move some definitions of PatchV9[05/23] to PatchV10[11/23].

Updates in V9:
- Modify annotations in sdhci_get_vdd_value().

Updates in V8:
- Adjust the position of matching brackets.
- Add the initial value of the pwr in sdhci_uhs2_set_power().

Updates in V7:
- Add clear the power reg before setting a new value
in sdhci_uhs2_set_power().
- Add MMC_VDD_34_35 case and MMC_VDD_35_36 case in sdhci_get_vdd_value().
- Drop pwr variable in sdhci_get_vdd_value().

Updates in V6:
- Add mmc_opt_regulator_set_ocr().
- Remove unnecessary functions.

---

drivers/mmc/host/sdhci-uhs2.c | 48 +++++++++++++++++++++++++++
drivers/mmc/host/sdhci.c | 61 +++++++++++++++++++----------------
drivers/mmc/host/sdhci.h | 1 +
include/linux/mmc/host.h | 1 +
4 files changed, 83 insertions(+), 28 deletions(-)

diff --git a/drivers/mmc/host/sdhci-uhs2.c b/drivers/mmc/host/sdhci-uhs2.c
index dfc80a7f1bad..fc37a34629c2 100644
--- a/drivers/mmc/host/sdhci-uhs2.c
+++ b/drivers/mmc/host/sdhci-uhs2.c
@@ -57,6 +57,13 @@ EXPORT_SYMBOL_GPL(sdhci_uhs2_dump_regs);
* *
\*****************************************************************************/

+static inline int mmc_opt_regulator_set_ocr(struct mmc_host *mmc,
+ struct regulator *supply,
+ unsigned short vdd_bit)
+{
+ return IS_ERR_OR_NULL(supply) ? 0 : mmc_regulator_set_ocr(mmc, supply, vdd_bit);
+}
+
bool sdhci_uhs2_mode(struct sdhci_host *host)
{
return host->mmc->flags & MMC_UHS2_SUPPORT;
@@ -94,6 +101,47 @@ void sdhci_uhs2_reset(struct sdhci_host *host, u16 mask)
}
EXPORT_SYMBOL_GPL(sdhci_uhs2_reset);

+static void sdhci_uhs2_set_power(struct sdhci_host *host, unsigned char mode, unsigned short vdd)
+{
+ struct mmc_host *mmc = host->mmc;
+ u8 pwr = 0;
+
+ if (mode != MMC_POWER_OFF) {
+ pwr = sdhci_get_vdd_value(vdd);
+ if (!pwr)
+ WARN(1, "%s: Invalid vdd %#x\n",
+ mmc_hostname(host->mmc), vdd);
+ pwr |= SDHCI_VDD2_POWER_180;
+ }
+
+ if (host->pwr == pwr)
+ return;
+ host->pwr = pwr;
+
+ if (pwr == 0) {
+ sdhci_writeb(host, 0, SDHCI_POWER_CONTROL);
+
+ mmc_opt_regulator_set_ocr(mmc, mmc->supply.vmmc, 0);
+ mmc_opt_regulator_set_ocr(mmc, mmc->supply.vmmc2, 0);
+ } else {
+ mmc_opt_regulator_set_ocr(mmc, mmc->supply.vmmc, vdd);
+ /* support 1.8v only for now */
+ mmc_opt_regulator_set_ocr(mmc, mmc->supply.vmmc2, fls(MMC_VDD_165_195) - 1);
+
+ /* Clear the power reg before setting a new value */
+ sdhci_writeb(host, 0, SDHCI_POWER_CONTROL);
+
+ /* vdd first */
+ pwr |= SDHCI_POWER_ON;
+ sdhci_writeb(host, pwr & 0xf, SDHCI_POWER_CONTROL);
+ mdelay(5);
+
+ pwr |= SDHCI_VDD2_POWER_ON;
+ sdhci_writeb(host, pwr, SDHCI_POWER_CONTROL);
+ mdelay(5);
+ }
+}
+
/*****************************************************************************\
* *
* Driver init/exit *
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 753b251179f2..eca54a16e7fc 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -23,7 +23,7 @@
#include <linux/regulator/consumer.h>
#include <linux/pm_runtime.h>
#include <linux/of.h>
-
+#include <linux/bug.h>
#include <linux/leds.h>

#include <linux/mmc/mmc.h>
@@ -2061,41 +2061,46 @@ static void sdhci_set_power_reg(struct sdhci_host *host, unsigned char mode,
sdhci_writeb(host, 0, SDHCI_POWER_CONTROL);
}

+unsigned short sdhci_get_vdd_value(unsigned short vdd)
+{
+ switch (1 << vdd) {
+ case MMC_VDD_165_195:
+ /*
+ * Without a regulator, SDHCI does not support 2.0v
+ * so we only get here if the driver deliberately
+ * added the 2.0v range to ocr_avail. Map it to 1.8v
+ * for the purpose of turning on the power.
+ */
+ case MMC_VDD_20_21:
+ return SDHCI_POWER_180;
+ case MMC_VDD_29_30:
+ case MMC_VDD_30_31:
+ return SDHCI_POWER_300;
+ case MMC_VDD_32_33:
+ case MMC_VDD_33_34:
+ /*
+ * 3.4V ~ 3.6V are valid only for those platforms where it's
+ * known that the voltage range is supported by hardware.
+ */
+ case MMC_VDD_34_35:
+ case MMC_VDD_35_36:
+ return SDHCI_POWER_330;
+ default:
+ return 0;
+ }
+}
+EXPORT_SYMBOL_GPL(sdhci_get_vdd_value);
+
void sdhci_set_power_noreg(struct sdhci_host *host, unsigned char mode,
unsigned short vdd)
{
u8 pwr = 0;

if (mode != MMC_POWER_OFF) {
- switch (1 << vdd) {
- case MMC_VDD_165_195:
- /*
- * Without a regulator, SDHCI does not support 2.0v
- * so we only get here if the driver deliberately
- * added the 2.0v range to ocr_avail. Map it to 1.8v
- * for the purpose of turning on the power.
- */
- case MMC_VDD_20_21:
- pwr = SDHCI_POWER_180;
- break;
- case MMC_VDD_29_30:
- case MMC_VDD_30_31:
- pwr = SDHCI_POWER_300;
- break;
- case MMC_VDD_32_33:
- case MMC_VDD_33_34:
- /*
- * 3.4 ~ 3.6V are valid only for those platforms where it's
- * known that the voltage range is supported by hardware.
- */
- case MMC_VDD_34_35:
- case MMC_VDD_35_36:
- pwr = SDHCI_POWER_330;
- break;
- default:
+ pwr = sdhci_get_vdd_value(vdd);
+ if (!pwr) {
WARN(1, "%s: Invalid vdd %#x\n",
mmc_hostname(host->mmc), vdd);
- break;
}
}

diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
index 43ad3f4b7672..f3bd558b337f 100644
--- a/drivers/mmc/host/sdhci.h
+++ b/drivers/mmc/host/sdhci.h
@@ -837,6 +837,7 @@ void sdhci_set_power(struct sdhci_host *host, unsigned char mode,
void sdhci_set_power_and_bus_voltage(struct sdhci_host *host,
unsigned char mode,
unsigned short vdd);
+unsigned short sdhci_get_vdd_value(unsigned short vdd);
void sdhci_set_power_noreg(struct sdhci_host *host, unsigned char mode,
unsigned short vdd);
int sdhci_get_cd_nogpio(struct mmc_host *mmc);
diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index e38c45392079..1eba64228725 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -357,6 +357,7 @@ struct mmc_pwrseq;

struct mmc_supply {
struct regulator *vmmc; /* Card power supply */
+ struct regulator *vmmc2; /* UHS2 VDD2 power supply */
struct regulator *vqmmc; /* Optional Vccq supply */
struct regulator *vqmmc2; /* Optional supply for phy */
};
--
2.25.1