[PATCH 4.4 145/312] mmc: sdhci: Fix regression setting power on Trats2 board

From: Greg Kroah-Hartman
Date: Fri May 08 2020 - 08:42:52 EST

From: Adrian Hunter <adrian.hunter@xxxxxxxxx>

commit 1dceb0415aa0c6bc11dacdab47c9ef83a3604166 upstream.

Several commits relating to setting power have been introducing
problems by putting driver-specific rules into generic SDHCI code.

Krzysztof Kozlowski reported that after commit 918f4cbd4340 ("mmc:
sdhci: restore behavior when setting VDD via external regulator")
on Trats2 board there are warnings for invalid VDD value (2.8V):

[ 3.119656] ------------[ cut here ]------------
[ 3.119666] WARNING: CPU: 3 PID: 90 at
../drivers/mmc/host/sdhci.c:1234 sdhci_do_set_ios+0x4cc/0x5e0
[ 3.119669] mmc0: Invalid vdd 0x10
[ 3.119673] Modules linked in:
[ 3.119679] CPU: 3 PID: 90 Comm: kworker/3:1 Tainted: G W
4.5.0-next-20160324 #23
[ 3.119681] Hardware name: SAMSUNG EXYNOS (Flattened Device Tree)
[ 3.119690] Workqueue: events_freezable mmc_rescan
[ 3.119708] [<c010e0ac>] (unwind_backtrace) from [<c010ae10>]
(show_stack+0x10/0x14)
[ 3.119719] [<c010ae10>] (show_stack) from [<c0323260>]
(dump_stack+0x88/0x9c)
[ 3.119728] [<c0323260>] (dump_stack) from [<c011b754>] (__warn+0xe8/0x100)
[ 3.119734] [<c011b754>] (__warn) from [<c011b7a4>]
(warn_slowpath_fmt+0x38/0x48)
[ 3.119740] [<c011b7a4>] (warn_slowpath_fmt) from [<c0527d28>]
(sdhci_do_set_ios+0x4cc/0x5e0)
[ 3.119748] [<c0527d28>] (sdhci_do_set_ios) from [<c0528018>]
(sdhci_runtime_resume_host+0x60/0x114)
[ 3.119758] [<c0528018>] (sdhci_runtime_resume_host) from
[<c0402570>] (__rpm_callback+0x2c/0x60)
[ 3.119767] [<c0402570>] (__rpm_callback) from [<c04025c4>]
(rpm_callback+0x20/0x80)
[ 3.119773] [<c04025c4>] (rpm_callback) from [<c04034b8>]
(rpm_resume+0x36c/0x558)
[ 3.119780] [<c04034b8>] (rpm_resume) from [<c04036f0>]
(__pm_runtime_resume+0x4c/0x64)
[ 3.119788] [<c04036f0>] (__pm_runtime_resume) from [<c0512728>]
(__mmc_claim_host+0x170/0x1b0)
[ 3.119795] [<c0512728>] (__mmc_claim_host) from [<c0514e2c>]
(mmc_rescan+0x54/0x348)
[ 3.119807] [<c0514e2c>] (mmc_rescan) from [<c0130dac>]
(process_one_work+0x120/0x3f4)
[ 3.119815] [<c0130dac>] (process_one_work) from [<c01310b8>]
(worker_thread+0x38/0x554)
[ 3.119823] [<c01310b8>] (worker_thread) from [<c01365a4>]
(kthread+0xdc/0xf4)
[ 3.119831] [<c01365a4>] (kthread) from [<c0107878>]
(ret_from_fork+0x14/0x3c)
[ 3.119834] ---[ end trace a22d652aa3276886 ]---

Fix by adding a 'set_power' callback and restoring the default
behaviour prior to commit 918f4cbd4340 ("mmc: sdhci: restore
behavior when setting VDD via external regulator"). The desired
behaviour of that commit is gotten by having sdhci-pxav3 provide
its own set_power callback.

Reported-by: Krzysztof Kozlowski <k.kozlowski@xxxxxxxxxxx>
Link: http://lkml.kernel.org/r/CAJKOXPcGDnPm-Ykh6wHqV1YxfTaov5E8iVqBoBn4OJc7BnhgEQ@xxxxxxxxxxxxxx
Fixes: 918f4cbd4340 ("mmc: sdhci: restore behavior when setting VDD...)
Tested-by: Krzysztof Kozlowski <k.kozlowski@xxxxxxxxxxx>
Tested-by: Ludovic Desroches <ludovic.desroches@xxxxxxxxx>
Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx # v4.5+
Reviewed-by: Jisheng Zhang <jszhang@xxxxxxxxxxx>
Tested-by: Jisheng Zhang <jszhang@xxxxxxxxxxx>
Tested-by: Jaehoon Chung <jh80.chung@xxxxxxxxxxx>
Tested-by: Anand Moon <linux.amoon@xxxxxxxxx>
Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/mmc/host/sdhci-pxav3.c | 22 ++++++++++++++++++++++
drivers/mmc/host/sdhci.c | 39 ++++++++++++++++++++++++++++++---------
drivers/mmc/host/sdhci.h | 4 ++++
3 files changed, 56 insertions(+), 9 deletions(-)

--- a/drivers/mmc/host/sdhci-pxav3.c
+++ b/drivers/mmc/host/sdhci-pxav3.c
@@ -307,8 +307,30 @@ static void pxav3_set_uhs_signaling(stru
__func__, uhs, ctrl_2);
}

+static void pxav3_set_power(struct sdhci_host *host, unsigned char mode,
+ unsigned short vdd)
+{
+ struct mmc_host *mmc = host->mmc;
+ u8 pwr = host->pwr;
+
+ sdhci_set_power(host, mode, vdd);
+
+ if (host->pwr == pwr)
+ return;
+
+ if (host->pwr == 0)
+ vdd = 0;
+
+ if (!IS_ERR(mmc->supply.vmmc)) {
+ spin_unlock_irq(&host->lock);
+ mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, vdd);
+ spin_lock_irq(&host->lock);
+ }
+}
+
static const struct sdhci_ops pxav3_sdhci_ops = {
.set_clock = sdhci_set_clock,
+ .set_power = pxav3_set_power,
.platform_send_init_74_clocks = pxav3_gen_init_74_clocks,
.get_max_clock = sdhci_pltfm_clk_get_max_clock,
.set_bus_width = sdhci_set_bus_width,
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -1284,10 +1284,24 @@ clock_set:
}
EXPORT_SYMBOL_GPL(sdhci_set_clock);

-static void sdhci_set_power(struct sdhci_host *host, unsigned char mode,
- unsigned short vdd)
+static void sdhci_set_power_reg(struct sdhci_host *host, unsigned char mode,
+ unsigned short vdd)
{
struct mmc_host *mmc = host->mmc;
+
+ spin_unlock_irq(&host->lock);
+ mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, vdd);
+ spin_lock_irq(&host->lock);
+
+ if (mode != MMC_POWER_OFF)
+ sdhci_writeb(host, SDHCI_POWER_ON, SDHCI_POWER_CONTROL);
+ else
+ sdhci_writeb(host, 0, SDHCI_POWER_CONTROL);
+}
+
+void sdhci_set_power(struct sdhci_host *host, unsigned char mode,
+ unsigned short vdd)
+{
u8 pwr = 0;

if (mode != MMC_POWER_OFF) {
@@ -1319,7 +1333,6 @@ static void sdhci_set_power(struct sdhci
sdhci_writeb(host, 0, SDHCI_POWER_CONTROL);
if (host->quirks2 & SDHCI_QUIRK2_CARD_ON_NEEDS_BUS_ON)
sdhci_runtime_pm_bus_off(host);
- vdd = 0;
} else {
/*
* Spec says that we should clear the power reg before setting
@@ -1350,12 +1363,20 @@ static void sdhci_set_power(struct sdhci
if (host->quirks & SDHCI_QUIRK_DELAY_AFTER_POWER)
mdelay(10);
}
+}
+EXPORT_SYMBOL_GPL(sdhci_set_power);

- if (!IS_ERR(mmc->supply.vmmc)) {
- spin_unlock_irq(&host->lock);
- mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, vdd);
- spin_lock_irq(&host->lock);
- }
+static void __sdhci_set_power(struct sdhci_host *host, unsigned char mode,
+ unsigned short vdd)
+{
+ struct mmc_host *mmc = host->mmc;
+
+ if (host->ops->set_power)
+ host->ops->set_power(host, mode, vdd);
+ else if (!IS_ERR(mmc->supply.vmmc))
+ sdhci_set_power_reg(host, mode, vdd);
+ else
+ sdhci_set_power(host, mode, vdd);
}

/*****************************************************************************\
@@ -1505,7 +1526,7 @@ static void sdhci_do_set_ios(struct sdhc
}
}

- sdhci_set_power(host, ios->power_mode, ios->vdd);
+ __sdhci_set_power(host, ios->power_mode, ios->vdd);

if (host->ops->platform_send_init_74_clocks)
host->ops->platform_send_init_74_clocks(host, ios->power_mode);
--- a/drivers/mmc/host/sdhci.h
+++ b/drivers/mmc/host/sdhci.h
@@ -529,6 +529,8 @@ struct sdhci_ops {
#endif

void (*set_clock)(struct sdhci_host *host, unsigned int clock);
+ void (*set_power)(struct sdhci_host *host, unsigned char mode,
+ unsigned short vdd);

int (*enable_dma)(struct sdhci_host *host);
unsigned int (*get_max_clock)(struct sdhci_host *host);
@@ -660,6 +662,8 @@ static inline bool sdhci_sdio_irq_enable
}

void sdhci_set_clock(struct sdhci_host *host, unsigned int clock);
+void sdhci_set_power(struct sdhci_host *host, unsigned char mode,
+ unsigned short vdd);
void sdhci_set_bus_width(struct sdhci_host *host, int width);
void sdhci_reset(struct sdhci_host *host, u8 mask);
void sdhci_set_uhs_signaling(struct sdhci_host *host, unsigned timing);