[PATCH v2 1/5] mmc: host: sdhci-s3c: Add broken-voltage DT property for broken voltage quirk
From: Chris Ball <hidden>
Date: 2012-09-19 14:39:48
Hi, On Wed, Sep 19 2012, Jaehoon Chung wrote:
quoted
On Wed, Sep 19 2012, Tomasz Figa wrote:quoted
We could just check if the regulator provides the capability to change the voltage. I don't see any direct way of querying the regulator for provided capabilities (correct me if I'm just blind), but calling regulator_count_voltages() on the regulator and checking if the returned value is 1 should be enough to assume that the regulator is fixed.Sounds good, I agree. Are you able to test that the obvious patch below works on your fixed-regulator board? Jaehoon and Adrian, can you think of any reason why we shouldn't replace MMC_CAP2_BROKEN_VOLTAGE with the regulator_count_voltages() call below? Thanks.I think this is better than using MMC_CAP2_BROKEN_VOLTAGE. I tested with this..and working fine.
Great, here's the patch. Jaehoon, once this is merged, maybe you could help remove the uses of MMC_CAP2_BROKEN_VOLTAGE from arch/arm/mach-exynos and arch/arm/mach-s5pv210 now that they're no longer needed? Thanks, - Chris. Subject: [PATCH] mmc: core: Replace MMC_CAP2_BROKEN_VOLTAGE with test for fixed regulator Before this patch, we were using MMC_CAP2_BROKEN_VOLTAGE as a way to avoid calling regulator_set_voltage() on a fixed regulator, but that's just duplicating information that already exists -- we should test whether the regulator is fixed directly, instead of via a capability. This patch implements that test. We can't reclaim the capability bit just yet, since there are still boards in arch/arm/ that reference it; those references can be removed now. Reported-by: Tomasz Figa <redacted> Signed-off-by: Chris Ball <redacted> --- drivers/mmc/core/core.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-)
diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index 044cd01..6612163 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c@@ -1113,7 +1113,8 @@ int mmc_regulator_set_ocr(struct mmc_host *mmc, int tmp; int voltage; - /* REVISIT mmc_vddrange_to_ocrmask() may have set some + /* + * REVISIT mmc_vddrange_to_ocrmask() may have set some * bits this regulator doesn't quite support ... don't * be too picky, most cards and regulators are OK with * a 0.1V range goof (it's a small error percentage).
@@ -1127,12 +1128,13 @@ int mmc_regulator_set_ocr(struct mmc_host *mmc, max_uV = min_uV + 100 * 1000; } - /* avoid needless changes to this voltage; the regulator - * might not allow this operation + /* + * If we're using a fixed/static regulator, don't call + * regulator_set_voltage; it would fail. */ voltage = regulator_get_voltage(supply); - if (mmc->caps2 & MMC_CAP2_BROKEN_VOLTAGE) + if (regulator_count_voltages(supply) == 1) min_uV = max_uV = voltage; if (voltage < 0)
--
Chris Ball <cjb@laptop.org> <http://printf.net/>
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