* [PATCH v3 1/3] mmc: core: consistent handling of initial values
2014-11-06 13:46 [PATCH v3 0/3] mmc: core: hw_reset changes Johan Rudholm
@ 2014-11-06 13:46 ` Johan Rudholm
2014-11-11 9:45 ` Ulf Hansson
2014-11-06 13:46 ` [PATCH v3 2/3] mmc: core: turn hw_reset into a bus_ops Johan Rudholm
2014-11-06 13:46 ` [PATCH v3 3/3] mmc: sd: add hw_reset callback Johan Rudholm
2 siblings, 1 reply; 5+ messages in thread
From: Johan Rudholm @ 2014-11-06 13:46 UTC (permalink / raw)
To: linux-mmc, Chris Ball, Ulf Hansson
Cc: Adrian Hunter, Guennadi Liakhovetski, David Lanzendörfer,
Jesper Nilsson, Johan Rudholm
mmc_do_hw_reset(), mmc_power_up() and mmc_power_off() all set similar
initial values for bus_mode, bus_width, chip_select and timing. Let's
make this handling simpler and more consistent by sticking them
together in a common function. This will introduce small changes in
behavior in the following places:
mmc_power_off():
For SPI hosts, explicitly set bus_mode = MMC_BUSMODE_PUSHPULL and
chip_select = MMC_CS_HIGH, before we left them as they were.
For non-SPI hosts, set bus_mode = MMC_BUSMODE_PUSHPULL instead of
MMC_BUSMODE_OPENDRAIN as before.
These two changes should not be a problem since the device will be
powered off anyway.
mmc_do_hw_reset():
Always set bus_mode = MMC_BUSMODE_PUSHPULL, as required by SD/SDIO
cards. MMC cards require MMC_BUSMODE_OPENDRAIN, but this is taken
care of by mmc_init_card() and mmc_attach_mmc().
Signed-off-by: Johan Rudholm <johanru@axis.com>
---
drivers/mmc/core/core.c | 47 ++++++++++++++++++++++-------------------------
drivers/mmc/core/core.h | 1 +
2 files changed, 23 insertions(+), 25 deletions(-)
diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index a32bea2..5bda29b 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -1099,6 +1099,22 @@ void mmc_set_bus_width(struct mmc_host *host, unsigned int width)
mmc_host_clk_release(host);
}
+/*
+ * Set initial state after a power cycle or a hw_reset.
+ */
+void mmc_set_initial_state(struct mmc_host *host)
+{
+ if (mmc_host_is_spi(host))
+ host->ios.chip_select = MMC_CS_HIGH;
+ else
+ host->ios.chip_select = MMC_CS_DONTCARE;
+ host->ios.bus_mode = MMC_BUSMODE_PUSHPULL;
+ host->ios.bus_width = MMC_BUS_WIDTH_1;
+ host->ios.timing = MMC_TIMING_LEGACY;
+
+ mmc_set_ios(host);
+}
+
/**
* mmc_vdd_to_ocrbitnum - Convert a voltage to the OCR bit number
* @vdd: voltage (mV)
@@ -1537,15 +1553,9 @@ void mmc_power_up(struct mmc_host *host, u32 ocr)
mmc_host_clk_hold(host);
host->ios.vdd = fls(ocr) - 1;
- if (mmc_host_is_spi(host))
- host->ios.chip_select = MMC_CS_HIGH;
- else
- host->ios.chip_select = MMC_CS_DONTCARE;
- host->ios.bus_mode = MMC_BUSMODE_PUSHPULL;
host->ios.power_mode = MMC_POWER_UP;
- host->ios.bus_width = MMC_BUS_WIDTH_1;
- host->ios.timing = MMC_TIMING_LEGACY;
- mmc_set_ios(host);
+ /* Set initial state and call mmc_set_ios */
+ mmc_set_initial_state(host);
/* Try to set signal voltage to 3.3V but fall back to 1.8v or 1.2v */
if (__mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_330) == 0)
@@ -1585,14 +1595,9 @@ void mmc_power_off(struct mmc_host *host)
host->ios.clock = 0;
host->ios.vdd = 0;
- if (!mmc_host_is_spi(host)) {
- host->ios.bus_mode = MMC_BUSMODE_OPENDRAIN;
- host->ios.chip_select = MMC_CS_DONTCARE;
- }
host->ios.power_mode = MMC_POWER_OFF;
- host->ios.bus_width = MMC_BUS_WIDTH_1;
- host->ios.timing = MMC_TIMING_LEGACY;
- mmc_set_ios(host);
+ /* Set initial state and call mmc_set_ios */
+ mmc_set_initial_state(host);
/*
* Some configurations, such as the 802.11 SDIO card in the OLPC
@@ -2278,16 +2283,8 @@ static int mmc_do_hw_reset(struct mmc_host *host, int check)
}
}
- if (mmc_host_is_spi(host)) {
- host->ios.chip_select = MMC_CS_HIGH;
- host->ios.bus_mode = MMC_BUSMODE_PUSHPULL;
- } else {
- host->ios.chip_select = MMC_CS_DONTCARE;
- host->ios.bus_mode = MMC_BUSMODE_OPENDRAIN;
- }
- host->ios.bus_width = MMC_BUS_WIDTH_1;
- host->ios.timing = MMC_TIMING_LEGACY;
- mmc_set_ios(host);
+ /* Set initial state and call mmc_set_ios */
+ mmc_set_initial_state(host);
mmc_host_clk_release(host);
diff --git a/drivers/mmc/core/core.h b/drivers/mmc/core/core.h
index 443a584..d76597c 100644
--- a/drivers/mmc/core/core.h
+++ b/drivers/mmc/core/core.h
@@ -49,6 +49,7 @@ void mmc_set_driver_type(struct mmc_host *host, unsigned int drv_type);
void mmc_power_up(struct mmc_host *host, u32 ocr);
void mmc_power_off(struct mmc_host *host);
void mmc_power_cycle(struct mmc_host *host, u32 ocr);
+void mmc_set_initial_state(struct mmc_host *host);
static inline void mmc_delay(unsigned int ms)
{
--
1.7.2.5
^ permalink raw reply related [flat|nested] 5+ messages in thread* Re: [PATCH v3 1/3] mmc: core: consistent handling of initial values
2014-11-06 13:46 ` [PATCH v3 1/3] mmc: core: consistent handling of initial values Johan Rudholm
@ 2014-11-11 9:45 ` Ulf Hansson
0 siblings, 0 replies; 5+ messages in thread
From: Ulf Hansson @ 2014-11-11 9:45 UTC (permalink / raw)
To: Johan Rudholm
Cc: linux-mmc, Chris Ball, Adrian Hunter, Guennadi Liakhovetski,
David Lanzendörfer, Jesper Nilsson, Johan Rudholm
On 6 November 2014 14:46, Johan Rudholm <johan.rudholm@axis.com> wrote:
> mmc_do_hw_reset(), mmc_power_up() and mmc_power_off() all set similar
> initial values for bus_mode, bus_width, chip_select and timing. Let's
> make this handling simpler and more consistent by sticking them
> together in a common function. This will introduce small changes in
> behavior in the following places:
>
> mmc_power_off():
>
> For SPI hosts, explicitly set bus_mode = MMC_BUSMODE_PUSHPULL and
> chip_select = MMC_CS_HIGH, before we left them as they were.
>
> For non-SPI hosts, set bus_mode = MMC_BUSMODE_PUSHPULL instead of
> MMC_BUSMODE_OPENDRAIN as before.
>
> These two changes should not be a problem since the device will be
> powered off anyway.
>
> mmc_do_hw_reset():
>
> Always set bus_mode = MMC_BUSMODE_PUSHPULL, as required by SD/SDIO
> cards. MMC cards require MMC_BUSMODE_OPENDRAIN, but this is taken
> care of by mmc_init_card() and mmc_attach_mmc().
>
> Signed-off-by: Johan Rudholm <johanru@axis.com>
I decided to apply this one now for my next branch, thus we also get
some testing of it in linux-next.
If it turns out that it's causing issues, we need to come back to it.
For the rest of the patches I need some more time to review.
Thanks and kind regards
Uffe
> ---
> drivers/mmc/core/core.c | 47 ++++++++++++++++++++++-------------------------
> drivers/mmc/core/core.h | 1 +
> 2 files changed, 23 insertions(+), 25 deletions(-)
>
> diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
> index a32bea2..5bda29b 100644
> --- a/drivers/mmc/core/core.c
> +++ b/drivers/mmc/core/core.c
> @@ -1099,6 +1099,22 @@ void mmc_set_bus_width(struct mmc_host *host, unsigned int width)
> mmc_host_clk_release(host);
> }
>
> +/*
> + * Set initial state after a power cycle or a hw_reset.
> + */
> +void mmc_set_initial_state(struct mmc_host *host)
> +{
> + if (mmc_host_is_spi(host))
> + host->ios.chip_select = MMC_CS_HIGH;
> + else
> + host->ios.chip_select = MMC_CS_DONTCARE;
> + host->ios.bus_mode = MMC_BUSMODE_PUSHPULL;
> + host->ios.bus_width = MMC_BUS_WIDTH_1;
> + host->ios.timing = MMC_TIMING_LEGACY;
> +
> + mmc_set_ios(host);
> +}
> +
> /**
> * mmc_vdd_to_ocrbitnum - Convert a voltage to the OCR bit number
> * @vdd: voltage (mV)
> @@ -1537,15 +1553,9 @@ void mmc_power_up(struct mmc_host *host, u32 ocr)
> mmc_host_clk_hold(host);
>
> host->ios.vdd = fls(ocr) - 1;
> - if (mmc_host_is_spi(host))
> - host->ios.chip_select = MMC_CS_HIGH;
> - else
> - host->ios.chip_select = MMC_CS_DONTCARE;
> - host->ios.bus_mode = MMC_BUSMODE_PUSHPULL;
> host->ios.power_mode = MMC_POWER_UP;
> - host->ios.bus_width = MMC_BUS_WIDTH_1;
> - host->ios.timing = MMC_TIMING_LEGACY;
> - mmc_set_ios(host);
> + /* Set initial state and call mmc_set_ios */
> + mmc_set_initial_state(host);
>
> /* Try to set signal voltage to 3.3V but fall back to 1.8v or 1.2v */
> if (__mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_330) == 0)
> @@ -1585,14 +1595,9 @@ void mmc_power_off(struct mmc_host *host)
> host->ios.clock = 0;
> host->ios.vdd = 0;
>
> - if (!mmc_host_is_spi(host)) {
> - host->ios.bus_mode = MMC_BUSMODE_OPENDRAIN;
> - host->ios.chip_select = MMC_CS_DONTCARE;
> - }
> host->ios.power_mode = MMC_POWER_OFF;
> - host->ios.bus_width = MMC_BUS_WIDTH_1;
> - host->ios.timing = MMC_TIMING_LEGACY;
> - mmc_set_ios(host);
> + /* Set initial state and call mmc_set_ios */
> + mmc_set_initial_state(host);
>
> /*
> * Some configurations, such as the 802.11 SDIO card in the OLPC
> @@ -2278,16 +2283,8 @@ static int mmc_do_hw_reset(struct mmc_host *host, int check)
> }
> }
>
> - if (mmc_host_is_spi(host)) {
> - host->ios.chip_select = MMC_CS_HIGH;
> - host->ios.bus_mode = MMC_BUSMODE_PUSHPULL;
> - } else {
> - host->ios.chip_select = MMC_CS_DONTCARE;
> - host->ios.bus_mode = MMC_BUSMODE_OPENDRAIN;
> - }
> - host->ios.bus_width = MMC_BUS_WIDTH_1;
> - host->ios.timing = MMC_TIMING_LEGACY;
> - mmc_set_ios(host);
> + /* Set initial state and call mmc_set_ios */
> + mmc_set_initial_state(host);
>
> mmc_host_clk_release(host);
>
> diff --git a/drivers/mmc/core/core.h b/drivers/mmc/core/core.h
> index 443a584..d76597c 100644
> --- a/drivers/mmc/core/core.h
> +++ b/drivers/mmc/core/core.h
> @@ -49,6 +49,7 @@ void mmc_set_driver_type(struct mmc_host *host, unsigned int drv_type);
> void mmc_power_up(struct mmc_host *host, u32 ocr);
> void mmc_power_off(struct mmc_host *host);
> void mmc_power_cycle(struct mmc_host *host, u32 ocr);
> +void mmc_set_initial_state(struct mmc_host *host);
>
> static inline void mmc_delay(unsigned int ms)
> {
> --
> 1.7.2.5
>
^ permalink raw reply [flat|nested] 5+ messages in thread
* [PATCH v3 2/3] mmc: core: turn hw_reset into a bus_ops
2014-11-06 13:46 [PATCH v3 0/3] mmc: core: hw_reset changes Johan Rudholm
2014-11-06 13:46 ` [PATCH v3 1/3] mmc: core: consistent handling of initial values Johan Rudholm
@ 2014-11-06 13:46 ` Johan Rudholm
2014-11-06 13:46 ` [PATCH v3 3/3] mmc: sd: add hw_reset callback Johan Rudholm
2 siblings, 0 replies; 5+ messages in thread
From: Johan Rudholm @ 2014-11-06 13:46 UTC (permalink / raw)
To: linux-mmc, Chris Ball, Ulf Hansson
Cc: Adrian Hunter, Guennadi Liakhovetski, David Lanzendörfer,
Jesper Nilsson, Johan Rudholm
Move the (e)MMC specific hw_reset code from core.c into mmc.c and call
it from the new bus_ops member hw_reset. This also lets us add code
for resetting SD cards as well.
Signed-off-by: Johan Rudholm <johanru@axis.com>
---
drivers/mmc/core/core.c | 56 +++++++++++++++-------------------------------
drivers/mmc/core/core.h | 5 ++++
drivers/mmc/core/mmc.c | 40 +++++++++++++++++++++++++++++++++
3 files changed, 63 insertions(+), 38 deletions(-)
diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index 5bda29b..63ce146 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -2242,67 +2242,47 @@ static void mmc_hw_reset_for_init(struct mmc_host *host)
mmc_host_clk_release(host);
}
-int mmc_can_reset(struct mmc_card *card)
-{
- u8 rst_n_function;
-
- if (!mmc_card_mmc(card))
- return 0;
- rst_n_function = card->ext_csd.rst_n_function;
- if ((rst_n_function & EXT_CSD_RST_N_EN_MASK) != EXT_CSD_RST_N_ENABLED)
- return 0;
- return 1;
-}
-EXPORT_SYMBOL(mmc_can_reset);
-
+/* Reset card in a bus-specific way */
static int mmc_do_hw_reset(struct mmc_host *host, int check)
{
- struct mmc_card *card = host->card;
-
- if (!(host->caps & MMC_CAP_HW_RESET) || !host->ops->hw_reset)
- return -EOPNOTSUPP;
+ int ret;
- if (!card)
+ if (!host->card)
return -EINVAL;
- if (!mmc_can_reset(card))
+ if (!host->bus_ops || !host->bus_ops->hw_reset ||
+ host->bus_ops->hw_reset(host, MMC_HW_RESET_TEST))
return -EOPNOTSUPP;
- mmc_host_clk_hold(host);
- mmc_set_clock(host, host->f_init);
+ ret = host->bus_ops->hw_reset(host, check);
- host->ops->hw_reset(host);
-
- /* If the reset has happened, then a status command will fail */
- if (check) {
- u32 status;
-
- if (!mmc_send_status(card, &status)) {
- mmc_host_clk_release(host);
- return -ENOSYS;
- }
- }
-
- /* Set initial state and call mmc_set_ios */
- mmc_set_initial_state(host);
+ if (check == MMC_HW_RESET_TEST_CARD)
+ return ret;
- mmc_host_clk_release(host);
+ pr_warn("%s: tried to reset card (status %d)\n",
+ mmc_hostname(host), ret);
return host->bus_ops->power_restore(host);
}
int mmc_hw_reset(struct mmc_host *host)
{
- return mmc_do_hw_reset(host, 0);
+ return mmc_do_hw_reset(host, MMC_HW_RESET_RESET);
}
EXPORT_SYMBOL(mmc_hw_reset);
int mmc_hw_reset_check(struct mmc_host *host)
{
- return mmc_do_hw_reset(host, 1);
+ return mmc_do_hw_reset(host, MMC_HW_RESET_CHECK);
}
EXPORT_SYMBOL(mmc_hw_reset_check);
+int mmc_can_reset(struct mmc_card *card)
+{
+ return mmc_do_hw_reset(card->host, MMC_HW_RESET_TEST_CARD);
+}
+EXPORT_SYMBOL(mmc_can_reset);
+
static int mmc_rescan_try_freq(struct mmc_host *host, unsigned freq)
{
host->f_init = freq;
diff --git a/drivers/mmc/core/core.h b/drivers/mmc/core/core.h
index d76597c..f6e0a52 100644
--- a/drivers/mmc/core/core.h
+++ b/drivers/mmc/core/core.h
@@ -27,6 +27,11 @@ struct mmc_bus_ops {
int (*power_restore)(struct mmc_host *);
int (*alive)(struct mmc_host *);
int (*shutdown)(struct mmc_host *);
+ int (*hw_reset)(struct mmc_host *, int);
+#define MMC_HW_RESET_RESET 0
+#define MMC_HW_RESET_TEST 1
+#define MMC_HW_RESET_CHECK 2
+#define MMC_HW_RESET_TEST_CARD 3
};
void mmc_attach_bus(struct mmc_host *host, const struct mmc_bus_ops *ops);
diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index 02ad792..7ffa3f2 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -1821,6 +1821,45 @@ static int mmc_power_restore(struct mmc_host *host)
return ret;
}
+static int mmc_mmc_hw_reset(struct mmc_host *host, int test)
+{
+ struct mmc_card *card = host->card;
+ u8 rst_n_function;
+
+ rst_n_function = card->ext_csd.rst_n_function;
+ if ((rst_n_function & EXT_CSD_RST_N_EN_MASK) != EXT_CSD_RST_N_ENABLED)
+ return -EOPNOTSUPP;
+
+ if (test == MMC_HW_RESET_TEST_CARD)
+ return 0;
+
+ if (!(host->caps & MMC_CAP_HW_RESET) || !host->ops->hw_reset)
+ return -EOPNOTSUPP;
+
+ if (test == MMC_HW_RESET_TEST)
+ return 0;
+
+ mmc_host_clk_hold(host);
+ mmc_set_clock(host, host->f_init);
+
+ host->ops->hw_reset(host);
+
+ if (test == MMC_HW_RESET_CHECK) {
+ u32 status;
+
+ if (!mmc_send_status(card, &status)) {
+ mmc_host_clk_release(host);
+ return -ENOSYS;
+ }
+ }
+
+ mmc_set_initial_state(host);
+
+ mmc_host_clk_release(host);
+
+ return 0;
+}
+
static const struct mmc_bus_ops mmc_ops = {
.remove = mmc_remove,
.detect = mmc_detect,
@@ -1831,6 +1870,7 @@ static const struct mmc_bus_ops mmc_ops = {
.power_restore = mmc_power_restore,
.alive = mmc_alive,
.shutdown = mmc_shutdown,
+ .hw_reset = mmc_mmc_hw_reset,
};
/*
--
1.7.2.5
^ permalink raw reply related [flat|nested] 5+ messages in thread* [PATCH v3 3/3] mmc: sd: add hw_reset callback
2014-11-06 13:46 [PATCH v3 0/3] mmc: core: hw_reset changes Johan Rudholm
2014-11-06 13:46 ` [PATCH v3 1/3] mmc: core: consistent handling of initial values Johan Rudholm
2014-11-06 13:46 ` [PATCH v3 2/3] mmc: core: turn hw_reset into a bus_ops Johan Rudholm
@ 2014-11-06 13:46 ` Johan Rudholm
2 siblings, 0 replies; 5+ messages in thread
From: Johan Rudholm @ 2014-11-06 13:46 UTC (permalink / raw)
To: linux-mmc, Chris Ball, Ulf Hansson
Cc: Adrian Hunter, Guennadi Liakhovetski, David Lanzendörfer,
Jesper Nilsson, Johan Rudholm
Enable power cycle and re-initialization of SD cards via the hw_reset
bus_ops. Power cycling a buggy SD card sometimes helps it get back on
track.
Signed-off-by: Johan Rudholm <johanru@axis.com>
---
drivers/mmc/core/sd.c | 13 +++++++++++++
1 files changed, 13 insertions(+), 0 deletions(-)
diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c
index d90a6de..a7fa124 100644
--- a/drivers/mmc/core/sd.c
+++ b/drivers/mmc/core/sd.c
@@ -1180,6 +1180,18 @@ static int mmc_sd_runtime_resume(struct mmc_host *host)
return 0;
}
+static int mmc_sd_hw_reset(struct mmc_host *host, int test)
+{
+ struct mmc_card *card = host->card;
+
+ if (test == MMC_HW_RESET_TEST || test == MMC_HW_RESET_TEST_CARD)
+ return 0;
+
+ mmc_power_cycle(host, card->ocr);
+
+ return 0;
+}
+
static int mmc_sd_power_restore(struct mmc_host *host)
{
int ret;
@@ -1201,6 +1213,7 @@ static const struct mmc_bus_ops mmc_sd_ops = {
.power_restore = mmc_sd_power_restore,
.alive = mmc_sd_alive,
.shutdown = mmc_sd_suspend,
+ .hw_reset = mmc_sd_hw_reset,
};
/*
--
1.7.2.5
^ permalink raw reply related [flat|nested] 5+ messages in thread