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authormerge <null@invalid>2009-01-22 13:55:32 +0000
committerAndy Green <agreen@octopus.localdomain>2009-01-22 13:55:32 +0000
commitaa6f5ffbdba45aa8e19e5048648fc6c7b25376d3 (patch)
treefbb786d0ac6f8a774fd834e9ce951197e60fbffa /drivers/mmc/core
parentf2d78193eae5dccd3d588d2c8ea0866efc368332 (diff)
MERGE-via-pending-tracking-hist-MERGE-via-stable-tracking-MERGE-via-mokopatches-tracking-fix-stray-endmenu-patch-1232632040-1232632141
pending-tracking-hist top was MERGE-via-stable-tracking-MERGE-via-mokopatches-tracking-fix-stray-endmenu-patch-1232632040-1232632141 / fdf777a63bcb59e0dfd78bfe2c6242e01f6d4eb9 ... parent commitmessage: From: merge <null@invalid> MERGE-via-stable-tracking-hist-MERGE-via-mokopatches-tracking-fix-stray-endmenu-patch-1232632040 stable-tracking-hist top was MERGE-via-mokopatches-tracking-fix-stray-endmenu-patch-1232632040 / 90463bfd2d5a3c8b52f6e6d71024a00e052b0ced ... parent commitmessage: From: merge <null@invalid> MERGE-via-mokopatches-tracking-hist-fix-stray-endmenu-patch mokopatches-tracking-hist top was fix-stray-endmenu-patch / 3630e0be570de8057e7f8d2fe501ed353cdf34e6 ... parent commitmessage: From: Andy Green <andy@openmoko.com> fix-stray-endmenu.patch Signed-off-by: Andy Green <andy@openmoko.com>
Diffstat (limited to 'drivers/mmc/core')
-rw-r--r--drivers/mmc/core/core.c77
-rw-r--r--drivers/mmc/core/mmc.c18
2 files changed, 91 insertions, 4 deletions
diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index 56988ff4732..72b972f2dbe 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -20,6 +20,7 @@
#include <linux/err.h>
#include <linux/leds.h>
#include <linux/scatterlist.h>
+#include <linux/log2.h>
#include <linux/mmc/card.h>
#include <linux/mmc/host.h>
@@ -449,6 +450,80 @@ void mmc_set_bus_width(struct mmc_host *host, unsigned int width)
mmc_set_ios(host);
}
+/**
+ * mmc_vdd_to_ocrbitnum - Convert a voltage to the OCR bit number
+ * @vdd: voltage (mV)
+ * @low_bits: prefer low bits in boundary cases
+ *
+ * This function returns the OCR bit number according to the provided @vdd
+ * value. If conversion is not possible a negative errno value returned.
+ *
+ * Depending on the @low_bits flag the function prefers low or high OCR bits
+ * on boundary voltages. For example,
+ * with @low_bits = true, 3300 mV translates to ilog2(MMC_VDD_32_33);
+ * with @low_bits = false, 3300 mV translates to ilog2(MMC_VDD_33_34);
+ *
+ * Any value in the [1951:1999] range translates to the ilog2(MMC_VDD_20_21).
+ */
+static int mmc_vdd_to_ocrbitnum(int vdd, bool low_bits)
+{
+ const int max_bit = ilog2(MMC_VDD_35_36);
+ int bit;
+
+ if (vdd < 1650 || vdd > 3600)
+ return -EINVAL;
+
+ if (vdd >= 1650 && vdd <= 1950)
+ return ilog2(MMC_VDD_165_195);
+
+ if (low_bits)
+ vdd -= 1;
+
+ /* Base 2000 mV, step 100 mV, bit's base 8. */
+ bit = (vdd - 2000) / 100 + 8;
+ if (bit > max_bit)
+ return max_bit;
+ return bit;
+}
+
+/**
+ * mmc_vddrange_to_ocrmask - Convert a voltage range to the OCR mask
+ * @vdd_min: minimum voltage value (mV)
+ * @vdd_max: maximum voltage value (mV)
+ *
+ * This function returns the OCR mask bits according to the provided @vdd_min
+ * and @vdd_max values. If conversion is not possible the function returns 0.
+ *
+ * Notes wrt boundary cases:
+ * This function sets the OCR bits for all boundary voltages, for example
+ * [3300:3400] range is translated to MMC_VDD_32_33 | MMC_VDD_33_34 |
+ * MMC_VDD_34_35 mask.
+ */
+u32 mmc_vddrange_to_ocrmask(int vdd_min, int vdd_max)
+{
+ u32 mask = 0;
+
+ if (vdd_max < vdd_min)
+ return 0;
+
+ /* Prefer high bits for the boundary vdd_max values. */
+ vdd_max = mmc_vdd_to_ocrbitnum(vdd_max, false);
+ if (vdd_max < 0)
+ return 0;
+
+ /* Prefer low bits for the boundary vdd_min values. */
+ vdd_min = mmc_vdd_to_ocrbitnum(vdd_min, true);
+ if (vdd_min < 0)
+ return 0;
+
+ /* Fill the mask, from max bit to min bit. */
+ while (vdd_max >= vdd_min)
+ mask |= 1 << vdd_max--;
+
+ return mask;
+}
+EXPORT_SYMBOL(mmc_vddrange_to_ocrmask);
+
/*
* Mask off any voltages we don't support and select
* the lowest voltage
@@ -468,6 +543,8 @@ u32 mmc_select_voltage(struct mmc_host *host, u32 ocr)
host->ios.vdd = bit;
mmc_set_ios(host);
} else {
+ pr_warning("%s: host doesn't support card's voltages\n",
+ mmc_hostname(host));
ocr = 0;
}
diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index fdd7c760be8..c232d11a7ed 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -434,13 +434,24 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr,
* Activate wide bus (if supported).
*/
if ((card->csd.mmca_vsn >= CSD_SPEC_VER_4) &&
- (host->caps & MMC_CAP_4_BIT_DATA)) {
+ (host->caps & (MMC_CAP_4_BIT_DATA | MMC_CAP_8_BIT_DATA))) {
+ unsigned ext_csd_bit, bus_width;
+
+ if (host->caps & MMC_CAP_8_BIT_DATA) {
+ ext_csd_bit = EXT_CSD_BUS_WIDTH_8;
+ bus_width = MMC_BUS_WIDTH_8;
+ } else {
+ ext_csd_bit = EXT_CSD_BUS_WIDTH_4;
+ bus_width = MMC_BUS_WIDTH_4;
+ }
+
err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
- EXT_CSD_BUS_WIDTH, EXT_CSD_BUS_WIDTH_4);
+ EXT_CSD_BUS_WIDTH, ext_csd_bit);
+
if (err)
goto free_card;
- mmc_set_bus_width(card->host, MMC_BUS_WIDTH_4);
+ mmc_set_bus_width(card->host, bus_width);
}
if (!oldcard)
@@ -624,4 +635,3 @@ err:
return err;
}
-