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-rw-r--r--drivers/mmc/core/mmc.c96
1 files changed, 96 insertions, 0 deletions
diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index 7adc30d..c2334d6 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -532,6 +532,86 @@ static struct device_type mmc_type = {
};
/*
+ * Select the PowerClass for the current bus width
+ * If power class is defined for 4/8 bit bus in the
+ * extended CSD register, select it by executing the
+ * mmc_switch command.
+ */
+static int mmc_select_powerclass(struct mmc_card *card,
+ unsigned int bus_width, u8 *ext_csd)
+{
+ int err = 0;
+ unsigned int pwrclass_val;
+ unsigned int index = 0;
+ struct mmc_host *host;
+
+ BUG_ON(!card);
+
+ host = card->host;
+ BUG_ON(!host);
+
+ if (ext_csd == NULL)
+ return 0;
+
+ /* Power class selection is supported for versions >= 4.0 */
+ if (card->csd.mmca_vsn < CSD_SPEC_VER_4)
+ return 0;
+
+ /* Power class values are defined only for 4/8 bit bus */
+ if (bus_width == EXT_CSD_BUS_WIDTH_1)
+ return 0;
+
+ switch (1 << host->ios.vdd) {
+ case MMC_VDD_165_195:
+ if (host->ios.clock <= 26000000)
+ index = EXT_CSD_PWR_CL_26_195;
+ else if (host->ios.clock <= 52000000)
+ index = (bus_width <= EXT_CSD_BUS_WIDTH_8) ?
+ EXT_CSD_PWR_CL_52_195 :
+ EXT_CSD_PWR_CL_DDR_52_195;
+ else if (host->ios.clock <= 200000000)
+ index = EXT_CSD_PWR_CL_200_195;
+ break;
+ case MMC_VDD_32_33:
+ case MMC_VDD_33_34:
+ case MMC_VDD_34_35:
+ case MMC_VDD_35_36:
+ if (host->ios.clock <= 26000000)
+ index = EXT_CSD_PWR_CL_26_360;
+ else if (host->ios.clock <= 52000000)
+ index = (bus_width <= EXT_CSD_BUS_WIDTH_8) ?
+ EXT_CSD_PWR_CL_52_360 :
+ EXT_CSD_PWR_CL_DDR_52_360;
+ else if (host->ios.clock <= 200000000)
+ index = EXT_CSD_PWR_CL_200_360;
+ break;
+ default:
+ pr_warning("%s: Voltage range not supported "
+ "for power class.\n", mmc_hostname(host));
+ return -EINVAL;
+ }
+
+ pwrclass_val = ext_csd[index];
+
+ if (bus_width & (EXT_CSD_BUS_WIDTH_8 | EXT_CSD_DDR_BUS_WIDTH_8))
+ pwrclass_val = (pwrclass_val & EXT_CSD_PWR_CL_8BIT_MASK) >>
+ EXT_CSD_PWR_CL_8BIT_SHIFT;
+ else
+ pwrclass_val = (pwrclass_val & EXT_CSD_PWR_CL_4BIT_MASK) >>
+ EXT_CSD_PWR_CL_4BIT_SHIFT;
+
+ /* If the power class is different from the default value */
+ if (pwrclass_val > 0) {
+ err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
+ EXT_CSD_POWER_CLASS,
+ pwrclass_val,
+ 0);
+ }
+
+ return err;
+}
+
+/*
* Handle the detection and initialisation of a card.
*
* In the case of a resume, "oldcard" will contain the card
@@ -787,6 +867,14 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr,
bus_width = bus_widths[idx];
if (bus_width == MMC_BUS_WIDTH_1)
ddr = 0; /* no DDR for 1-bit width */
+ err = mmc_select_powerclass(card, ext_csd_bits[idx][0],
+ ext_csd);
+ if (err)
+ pr_err("%s: power class selection to "
+ "bus width %d failed\n",
+ mmc_hostname(card->host),
+ 1 << bus_width);
+
err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
EXT_CSD_BUS_WIDTH,
ext_csd_bits[idx][0],
@@ -810,6 +898,14 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr,
}
if (!err && ddr) {
+ err = mmc_select_powerclass(card, ext_csd_bits[idx][1],
+ ext_csd);
+ if (err)
+ pr_err("%s: power class selection to "
+ "bus width %d ddr %d failed\n",
+ mmc_hostname(card->host),
+ 1 << bus_width, ddr);
+
err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
EXT_CSD_BUS_WIDTH,
ext_csd_bits[idx][1],