Hi Jean-Jacques,
On 15 May 2017 at 08:18, Jean-Jacques Hiblot jjhiblot@ti.com wrote:
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.
If there is no regulator, then how about checking the error return value, and if it is -ENODEV, continue. But any other error, you exit.
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