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path: root/drivers/mmc/core/sd.c
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Diffstat (limited to 'drivers/mmc/core/sd.c')
-rw-r--r--drivers/mmc/core/sd.c171
1 files changed, 79 insertions, 92 deletions
diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c
index b2b43f624b9..74972c241df 100644
--- a/drivers/mmc/core/sd.c
+++ b/drivers/mmc/core/sd.c
@@ -244,7 +244,7 @@ static int mmc_read_ssr(struct mmc_card *card)
* bitfield positions accordingly.
*/
au = UNSTUFF_BITS(ssr, 428 - 384, 4);
- if (au > 0 || au <= 9) {
+ if (au > 0 && au <= 9) {
card->ssr.au = 1 << (au + 4);
es = UNSTUFF_BITS(ssr, 408 - 384, 16);
et = UNSTUFF_BITS(ssr, 402 - 384, 6);
@@ -290,8 +290,12 @@ static int mmc_read_switch(struct mmc_card *card)
return -ENOMEM;
}
- /* Find out the supported Bus Speed Modes. */
- err = mmc_sd_switch(card, 0, 0, 1, status);
+ /*
+ * Find out the card's support bits with a mode 0 operation.
+ * The argument does not matter, as the support bits do not
+ * change with the arguments.
+ */
+ err = mmc_sd_switch(card, 0, 0, 0, status);
if (err) {
/*
* If the host or the card can't do the switch,
@@ -312,46 +316,8 @@ static int mmc_read_switch(struct mmc_card *card)
if (card->scr.sda_spec3) {
card->sw_caps.sd3_bus_mode = status[13];
-
- /* Find out Driver Strengths supported by the card */
- err = mmc_sd_switch(card, 0, 2, 1, status);
- if (err) {
- /*
- * If the host or the card can't do the switch,
- * fail more gracefully.
- */
- if (err != -EINVAL && err != -ENOSYS && err != -EFAULT)
- goto out;
-
- pr_warning("%s: problem reading "
- "Driver Strength.\n",
- mmc_hostname(card->host));
- err = 0;
-
- goto out;
- }
-
+ /* Driver Strengths supported by the card */
card->sw_caps.sd3_drv_type = status[9];
-
- /* Find out Current Limits supported by the card */
- err = mmc_sd_switch(card, 0, 3, 1, status);
- if (err) {
- /*
- * If the host or the card can't do the switch,
- * fail more gracefully.
- */
- if (err != -EINVAL && err != -ENOSYS && err != -EFAULT)
- goto out;
-
- pr_warning("%s: problem reading "
- "Current Limit.\n",
- mmc_hostname(card->host));
- err = 0;
-
- goto out;
- }
-
- card->sw_caps.sd3_curr_limit = status[7];
}
out:
@@ -551,60 +517,80 @@ static int sd_set_bus_speed_mode(struct mmc_card *card, u8 *status)
return 0;
}
+/* Get host's max current setting at its current voltage */
+static u32 sd_get_host_max_current(struct mmc_host *host)
+{
+ u32 voltage, max_current;
+
+ voltage = 1 << host->ios.vdd;
+ switch (voltage) {
+ case MMC_VDD_165_195:
+ max_current = host->max_current_180;
+ break;
+ case MMC_VDD_29_30:
+ case MMC_VDD_30_31:
+ max_current = host->max_current_300;
+ break;
+ case MMC_VDD_32_33:
+ case MMC_VDD_33_34:
+ max_current = host->max_current_330;
+ break;
+ default:
+ max_current = 0;
+ }
+
+ return max_current;
+}
+
static int sd_set_current_limit(struct mmc_card *card, u8 *status)
{
- int current_limit = 0;
+ int current_limit = SD_SET_CURRENT_NO_CHANGE;
int err;
+ u32 max_current;
/*
* Current limit switch is only defined for SDR50, SDR104, and DDR50
- * bus speed modes. For other bus speed modes, we set the default
- * current limit of 200mA.
+ * bus speed modes. For other bus speed modes, we do not change the
+ * current limit.
*/
- if ((card->sd_bus_speed == UHS_SDR50_BUS_SPEED) ||
- (card->sd_bus_speed == UHS_SDR104_BUS_SPEED) ||
- (card->sd_bus_speed == UHS_DDR50_BUS_SPEED)) {
- if (card->host->caps & MMC_CAP_MAX_CURRENT_800) {
- if (card->sw_caps.sd3_curr_limit & SD_MAX_CURRENT_800)
- current_limit = SD_SET_CURRENT_LIMIT_800;
- else if (card->sw_caps.sd3_curr_limit &
- SD_MAX_CURRENT_600)
- current_limit = SD_SET_CURRENT_LIMIT_600;
- else if (card->sw_caps.sd3_curr_limit &
- SD_MAX_CURRENT_400)
- current_limit = SD_SET_CURRENT_LIMIT_400;
- else if (card->sw_caps.sd3_curr_limit &
- SD_MAX_CURRENT_200)
- current_limit = SD_SET_CURRENT_LIMIT_200;
- } else if (card->host->caps & MMC_CAP_MAX_CURRENT_600) {
- if (card->sw_caps.sd3_curr_limit & SD_MAX_CURRENT_600)
- current_limit = SD_SET_CURRENT_LIMIT_600;
- else if (card->sw_caps.sd3_curr_limit &
- SD_MAX_CURRENT_400)
- current_limit = SD_SET_CURRENT_LIMIT_400;
- else if (card->sw_caps.sd3_curr_limit &
- SD_MAX_CURRENT_200)
- current_limit = SD_SET_CURRENT_LIMIT_200;
- } else if (card->host->caps & MMC_CAP_MAX_CURRENT_400) {
- if (card->sw_caps.sd3_curr_limit & SD_MAX_CURRENT_400)
- current_limit = SD_SET_CURRENT_LIMIT_400;
- else if (card->sw_caps.sd3_curr_limit &
- SD_MAX_CURRENT_200)
- current_limit = SD_SET_CURRENT_LIMIT_200;
- } else if (card->host->caps & MMC_CAP_MAX_CURRENT_200) {
- if (card->sw_caps.sd3_curr_limit & SD_MAX_CURRENT_200)
- current_limit = SD_SET_CURRENT_LIMIT_200;
- }
- } else
+ if ((card->sd_bus_speed != UHS_SDR50_BUS_SPEED) &&
+ (card->sd_bus_speed != UHS_SDR104_BUS_SPEED) &&
+ (card->sd_bus_speed != UHS_DDR50_BUS_SPEED))
+ return 0;
+
+ /*
+ * Host has different current capabilities when operating at
+ * different voltages, so find out its max current first.
+ */
+ max_current = sd_get_host_max_current(card->host);
+
+ /*
+ * We only check host's capability here, if we set a limit that is
+ * higher than the card's maximum current, the card will be using its
+ * maximum current, e.g. if the card's maximum current is 300ma, and
+ * when we set current limit to 200ma, the card will draw 200ma, and
+ * when we set current limit to 400/600/800ma, the card will draw its
+ * maximum 300ma from the host.
+ */
+ if (max_current >= 800)
+ current_limit = SD_SET_CURRENT_LIMIT_800;
+ else if (max_current >= 600)
+ current_limit = SD_SET_CURRENT_LIMIT_600;
+ else if (max_current >= 400)
+ current_limit = SD_SET_CURRENT_LIMIT_400;
+ else if (max_current >= 200)
current_limit = SD_SET_CURRENT_LIMIT_200;
- err = mmc_sd_switch(card, 1, 3, current_limit, status);
- if (err)
- return err;
+ if (current_limit != SD_SET_CURRENT_NO_CHANGE) {
+ err = mmc_sd_switch(card, 1, 3, current_limit, status);
+ if (err)
+ return err;
- if (((status[15] >> 4) & 0x0F) != current_limit)
- pr_warning("%s: Problem setting current limit!\n",
- mmc_hostname(card->host));
+ if (((status[15] >> 4) & 0x0F) != current_limit)
+ pr_warning("%s: Problem setting current limit!\n",
+ mmc_hostname(card->host));
+
+ }
return 0;
}
@@ -726,6 +712,7 @@ struct device_type sd_type = {
int mmc_sd_get_cid(struct mmc_host *host, u32 ocr, u32 *cid, u32 *rocr)
{
int err;
+ u32 max_current;
/*
* Since we're changing the OCR value, we seem to
@@ -753,9 +740,12 @@ int mmc_sd_get_cid(struct mmc_host *host, u32 ocr, u32 *cid, u32 *rocr)
MMC_CAP_UHS_SDR50 | MMC_CAP_UHS_SDR104 | MMC_CAP_UHS_DDR50))
ocr |= SD_OCR_S18R;
- /* If the host can supply more than 150mA, XPC should be set to 1. */
- if (host->caps & (MMC_CAP_SET_XPC_330 | MMC_CAP_SET_XPC_300 |
- MMC_CAP_SET_XPC_180))
+ /*
+ * If the host can supply more than 150mA at current voltage,
+ * XPC should be set to 1.
+ */
+ max_current = sd_get_host_max_current(host);
+ if (max_current > 150)
ocr |= SD_OCR_XPC;
try_again:
@@ -911,9 +901,6 @@ static int mmc_sd_init_card(struct mmc_host *host, u32 ocr,
BUG_ON(!host);
WARN_ON(!host->claimed);
- /* The initialization should be done at 3.3 V I/O voltage. */
- mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_330, 0);
-
err = mmc_sd_get_cid(host, ocr, cid, &rocr);
if (err)
return err;