linux-stable.git/drivers/mmc/core, branch v4.0.2

mmc: pwrseq_simple: fix error path in mmc_pwrseq_simple_alloc

2015-03-19T10:26:35+00:00

The current error-path code (when gpiod_get_index() reports
an error) can never free pwrseq->reset_gpios[0], but might
try to tree pwrseq->reset_gpios[-1], which has unfortunate
consequences.

Signed-off-by: NeilBrown 
Fixes: 934f1f48330ed695927a51fa068dc5d673f2da19
Acked-by: Javier Martinez Canillas 
Signed-off-by: Ulf Hansson 
Reported-by: Srinivas Kandagatla

mmc: pwrseq: add driver for emmc hardware reset

2015-02-04T08:45:09+00:00

This patch provides a simple mmc-pwrseq-emmc driver, which controls
single gpio line. It perform standard eMMC hw reset procedure, as
descibed by Jedec 4.4 specification. This procedure is performed just
after MMC core enabled power to the given mmc host (to fix possible
issues if bootloader has left eMMC card in initialized or unknown
state), and before performing complete system reboot (also in case of
emergency reboot call). The latter is needed on boards, which doesn't
have hardware reset logic connected to emmc card and (limited or broken)
ROM bootloaders are unable to read second stage from the emmc card if
the card is left in unknown or already initialized state.

Signed-off-by: Marek Szyprowski 
Signed-off-by: Ulf Hansson

mmc: core: Invoke mmc_pwrseq_post_power_on() prior MMC_POWER_ON state

2015-02-03T19:56:58+00:00

Host drivers have different ways to sends their "init stream" to the
card. Some need to do it as part of a request, some do it from the
->set_ios() callback in the MMC_POWER_ON state and some don't send an
"init stream" at all.

To be able to use the reset GPIOs from the simple MMC power sequence
provider, the card need to be powered and the "init stream" must not
have been sent.

To cope with these requirements, invoke mmc_pwrseq_post_power_on()
prior we change the state to MMC_POWER_ON in mmc_power_up().

Host drivers shall perform power up operations in the MMC_POWER_UP
state. Unfortunate three hosts (au1xmmc, cb710-mmc and toshsd) don't
conform to this expectation. Instead those ignore the MMC_POWER_UP
state and delays their power up operations to the MMC_POWER_ON state.

Those hosts needs to change their behavior to enable proper support for
the simple MMC power sequence provider.

Signed-off-by: Ulf Hansson 
Reviewed-by: Javier Martinez Canillas 
Tested-by: Javier Martinez Canillas

mmc: pwrseq_simple: Add optional reference clock support

2015-01-30T11:10:23+00:00

Some WLAN chips attached to a SDIO interface, need a reference clock.

Since this is very common, extend the prseq_simple driver to support
an optional clock that is enabled prior the card power up procedure.

Note: the external clock is optional. Thus an error is not returned
if the clock is not found.

Signed-off-by: Javier Martinez Canillas 
Signed-off-by: Ulf Hansson

mmc: pwrseq_simple: Extend to support more pins

2015-01-30T11:00:27+00:00

Many WLAN attached to a SDIO/MMC interface, needs more than one pin for
their reset sequence. For example, is very common for chips to have two
pins: one for reset and one for power enable.

This patch adds support for more reset pins to the pwrseq_simple driver
and instead hardcoding a fixed number, it uses the of_gpio_named_count()
since the MMC power sequence is only built when CONFIG_OF is enabled.

Signed-off-by: Javier Martinez Canillas 
Signed-off-by: Srinivas Kandagatla 
Signed-off-by: Ulf Hansson

mmc: Resolve BKOPS compatability issue

2015-01-29T10:15:12+00:00

This patch is coming to fix compatibility issue of BKOPS_EN  field of EXT_CSD.
In eMMC-5.1, BKOPS_EN was changed, and now it has two operational bits:
Bit 0 - MANUAL_EN
Bit 1 - AUTO_EN
In previous eMMC revisions, only Bit 0 was supported.

Signed-off-by: Alexey Skidanov 
Signed-off-by: Ulf Hansson

mmc: pwrseq_simple: Add support for a reset GPIO pin

2015-01-28T11:32:13+00:00

The need for reset GPIOs has several times been pointed out from
erlier posted patchsets. Especially some WLAN chips which are
attached to an SDIO interface may use a GPIO reset.

The reset GPIO is asserted at initialization and prior we start the
power up procedure. The GPIO will be de-asserted right after the power
has been provided to the card, from the ->post_power_on() callback.

Note, the reset GPIO is optional. Thus we don't return an error even if
we can't find a GPIO for the consumer.

Signed-off-by: Ulf Hansson 
Tested-by: Javier Martinez Canillas 
Reviewed-by: Javier Martinez Canillas

mmc: pwrseq: Initial support for the simple MMC power sequence provider

2015-01-28T11:32:07+00:00

To add the core part for the MMC power sequence, let's start by adding
initial support for the simple MMC power sequence provider.

In this initial step, the MMC power sequence node are fetched and the
compatible string for the simple MMC power sequence provider are
verified.

At this point we don't parse the node for any properties, but instead
that will be handled from following patches. Since there are no
properties supported yet, let's just implement the ->alloc() and the
->free() callbacks.

Signed-off-by: Ulf Hansson 
Tested-by: Javier Martinez Canillas 
Reviewed-by: Javier Martinez Canillas

mmc: core: Initial support for MMC power sequences

2015-01-28T11:31:12+00:00

System on chip designs may specify a specific MMC power sequence. To
successfully detect an (e)MMC/SD/SDIO card, that power sequence must
be followed while initializing the card.

To be able to handle these SOC specific power sequences, let's add a
MMC power sequence interface. It provides the following functions to
help the mmc core to deal with these power sequences.

mmc_pwrseq_alloc() - Invoked from mmc_of_parse(), to initialize data.
mmc_pwrseq_pre_power_on()- Invoked in the beginning of mmc_power_up().
mmc_pwrseq_post_power_on()- Invoked at the end in mmc_power_up().
mmc_pwrseq_power_off()- Invoked from mmc_power_off().
mmc_pwrseq_free() - Invoked from mmc_free_host(), to free data.

Each MMC power sequence provider will be responsible to implement a set
of callbacks. These callbacks mirrors the functions above.

This patch adds the skeleton, following patches will extend the core of
the MMC power sequence and add support for a specific simple MMC power
sequence.

Do note, since the mmc_pwrseq_alloc() is invoked from mmc_of_parse(),
host drivers needs to make use of this API to enable the support for
MMC power sequences. Moreover the MMC power sequence support depends on
CONFIG_OF.

Signed-off-by: Ulf Hansson 
Tested-by: Javier Martinez Canillas 
Reviewed-by: Javier Martinez Canillas

mmc: core: Move mmc_card_removed() into mmc_start_request()

2015-01-19T08:56:30+00:00

Both callers of mmc_start_request() call mmc_card_removed()
so move that call into mmc_start_request().

This patch is preparation for adding re-tuning support.

Signed-off-by: Adrian Hunter 
Signed-off-by: Ulf Hansson