On 15/05/2017 05:28, Simon Glass wrote:
Hi Jen-Jacques,
On 12 May 2017 at 12:16, Jean-Jacques Hiblot jjhiblot@ti.com wrote:
From: Kishon Vijay Abraham I kishon@ti.com
Add a new function *mmc_set_signal_voltage* in mmc core which can be used during mmc initialization to select the signal voltage. Platform driver should use the set_ios callback function to select the signal voltage.
Signed-off-by: Kishon Vijay Abraham I kishon@ti.com Signed-off-by: Jean-Jacques Hiblot jjhiblot@ti.com
drivers/mmc/mmc.c | 15 +++++++++++++++ include/mmc.h | 5 +++++ 2 files changed, 20 insertions(+)
diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c index 2ae6f1c..10af81d 100644 --- a/drivers/mmc/mmc.c +++ b/drivers/mmc/mmc.c @@ -29,6 +29,7 @@ static const unsigned int sd_au_size[] = { SZ_4M / 512, SZ_8M / 512, (SZ_8M + SZ_4M) / 512, SZ_16M / 512, (SZ_16M + SZ_8M) / 512, SZ_32M / 512, SZ_64M / 512, }; +static int mmc_set_signal_voltage(struct mmc *mmc, uint signal_voltage);
#if CONFIG_IS_ENABLED(MMC_TINY) static struct mmc mmc_static; @@ -1247,6 +1248,12 @@ struct mode_width_tuning { uint widths; };
+static int mmc_set_signal_voltage(struct mmc *mmc, uint signal_voltage) +{
mmc->signal_voltage = signal_voltage;return mmc_set_ios(mmc);+}
- static const struct mode_width_tuning sd_modes_by_pref[] = { { .mode = SD_HS,
@@ -1935,6 +1942,14 @@ int mmc_start_init(struct mmc *mmc) return err; #endif mmc->ddr_mode = 0;
/* First try to set 3.3V. If it fails set to 1.8V */err = mmc_set_signal_voltage(mmc, MMC_SIGNAL_VOLTAGE_330);if (err != 0)err = mmc_set_signal_voltage(mmc, MMC_SIGNAL_VOLTAGE_180);if (err != 0)printf("failed to set signal voltage\n");Return error?
Maybe we should. I don't know. Setting signal voltage is optional (at least for most modes), some platforms don't support it. So I wouldn't exit on this kind of error. Those 2 calls to mmc_set_signal_voltage() are here merely to turn on regulators before doing the card init. If setting voltage is required and fails, the init process won't go very far.
mmc_set_bus_width(mmc, 1); mmc_set_clock(mmc, 1);diff --git a/include/mmc.h b/include/mmc.h index 9f20eb4..89cb26c 100644 --- a/include/mmc.h +++ b/include/mmc.h @@ -266,6 +266,10 @@ #define ENHNCD_SUPPORT (0x2) #define PART_ENH_ATTRIB (0x1f)
+#define MMC_SIGNAL_VOLTAGE_330 1 +#define MMC_SIGNAL_VOLTAGE_180 2 +#define MMC_SIGNAL_VOLTAGE_120 3
- /* Maximum block size for MMC */ #define MMC_MAX_BLOCK_LEN 512
@@ -452,6 +456,7 @@ struct mmc { int high_capacity; uint bus_width; uint clock;
uint signal_voltage;Comment. What does this value mean? What units is it? Millivolts or something else?
it's more an enum than a value with a physical meaning (like mV). I'll change this in the next version to be a real enum.
uint card_caps; uint ocr; uint dsr;-- 1.9.1
Regards, Simon