linux-stable.git/drivers/mmc/core/core.c, branch v3.0

mmc: core: make erase timeout calculation allow for gated clock

2011-06-25T22:52:53+00:00

The erase timeout calculation may depend on clock rate
which is zero if the clock is gated, so use
mmc_host_clk_rate() which allows for that case.

Signed-off-by: Adrian Hunter 
Signed-off-by: Chris Ball

mmc: core: duplicated trial with same freq in mmc_rescan_try_freq()

2011-05-25T03:53:59+00:00

mmc_rescan_try_freq() tries to init two times with the last frequency.
For example, if host->f_min is 400KHz, we see the message below:

mmc1: mmc_rescan_try_freq: trying to init card at 400000 Hz
mmc1: mmc_rescan_try_freq: trying to init card at 400000 Hz

Andy Ross says that he didn't try this code on a board with an f_min
that exactly matches one of the table entries, which explains why the
bug wasn't detected.

Signed-off-by: Jaehoon Chung 
Signed-off-by: Kyungmin Park 
Cc: Andy Ross 
Signed-off-by: Chris Ball

mmc: core: add support for eMMC Dual Data Rate

2011-05-25T03:53:58+00:00

eMMC voltage change not required for 1.8V.  3.3V and 1.8V vcc
are capable of doing DDR. vccq of 1.8v is not required.

Signed-off-by: Philip Rakity 
Reviewed-by: Arindam Nath 
Signed-off-by: Chris Ball

mmc: core: eMMC signal voltage does not use CMD11

2011-05-25T03:53:58+00:00

eMMC chips do not use CMD11 when changing voltage.  Add extra
argument to call to indicate if CMD11 needs to be sent.

Signed-off-by: Philip Rakity 
Reviewed-by: Arindam Nath 
Signed-off-by: Chris Ball

mmc: core: clear MMC_PM_KEEP_POWER flag on resume

2011-05-25T03:53:56+00:00

Since the MMC_PM_KEEP_POWER flag should be set on each suspend,
it should also cleared on each resume.

Upon resuming, we have to know if power was kept
(for re-initialization, etc.), so clear it just after resuming.

Signed-off-by: Eliad Peller 
Signed-off-by: Chris Ball

mmc: sd: add support for driver type selection

2011-05-25T03:53:24+00:00

This patch adds support for setting driver strength during UHS-I
initialization procedure. Since UHS-I cards set S18A (bit 24) in
response to ACMD41, we use this as a base for UHS-I initialization.
We modify the parameter list of mmc_sd_get_cid() so that we can
save the ROCR from ACMD41 to check whether bit 24 is set.

We decide whether the Host Controller supports A, C, or D driver
type depending on the Capabilities register. Driver type B is
suported by default. We then set the appropriate driver type for
the card using CMD6 mode 1. As per Host Controller spec v3.00, we
set driver type for the host only if Preset Value Enable in the
Host Control2 register is not set. SDHCI_HOST_CONTROL has been
renamed to SDHCI_HOST_CONTROL1 to conform to the spec.

Tested by Zhangfei Gao with a Toshiba uhs card and general hs card,
on mmp2 in SDMA mode.

Signed-off-by: Arindam Nath 
Reviewed-by: Philip Rakity 
Tested-by: Philip Rakity 
Acked-by: Zhangfei Gao 
Signed-off-by: Chris Ball

mmc: sd: add support for signal voltage switch procedure

2011-05-25T01:04:38+00:00

Host Controller v3.00 adds another Capabilities register. Apart
from other things, this new register indicates whether the Host
Controller supports SDR50, SDR104, and DDR50 UHS-I modes. The spec
doesn't mention about explicit support for SDR12 and SDR25 UHS-I
modes, so the Host Controller v3.00 should support them by default.
Also if the controller supports SDR104 mode, it will also support
SDR50 mode as well. So depending on the host support, we set the
corresponding MMC_CAP_* flags. One more new register. Host Control2
is added in v3.00, which is used during Signal Voltage Switch
procedure described below.

Since as per v3.00 spec, UHS-I supported hosts should set S18R
to 1, we set S18R (bit 24) of OCR before sending ACMD41. We also
need to set XPC (bit 28) of OCR in case the host can supply >150mA.
This support is indicated by the Maximum Current Capabilities
register of the Host Controller.

If the response of ACMD41 has both CCS and S18A set, we start the
signal voltage switch procedure, which if successfull, will switch
the card from 3.3V signalling to 1.8V signalling. Signal voltage
switch procedure adds support for a new command CMD11 in the
Physical Layer Spec v3.01. As part of this procedure, we need to
set 1.8V Signalling Enable (bit 3) of Host Control2 register, which
if remains set after 5ms, means the switch to 1.8V signalling is
successfull. Otherwise, we clear bit 24 of OCR and retry the
initialization sequence. When we remove the card, and insert the
same or another card, we need to make sure that we start with 3.3V
signalling voltage. So we call mmc_set_signal_voltage() with
MMC_SIGNAL_VOLTAGE_330 set so that we are back to 3.3V signalling
voltage before we actually start initializing the card.

Tested by Zhangfei Gao with a Toshiba uhs card and general hs card,
on mmp2 in SDMA mode.

Signed-off-by: Arindam Nath 
Reviewed-by: Philip Rakity 
Tested-by: Philip Rakity 
Acked-by: Zhangfei Gao 
Signed-off-by: Chris Ball

mmc: initialize struct mmc_request at declaration time

2011-05-25T01:02:01+00:00

Converts from:
	struct mmc_request mrq;
	memset(&mrq, 0, sizeof(struct mmc_request));

to:
	struct mmc_request mrq = {0};

because it's shorter, as performant, and easier to work out whether
initialization has happened.

Signed-off-by: Chris Ball

mmc: initialize struct mmc_command at declaration time

2011-05-25T01:01:52+00:00

Converts from:
	struct mmc_command cmd;
	memset(&cmd, 0, sizeof(struct mmc_command));

to:
	struct mmc_command cmd = {0};

because it's shorter, as performant, and easier to work out whether
initialization has happened.

Signed-off-by: Chris Ball

mmc: core: Rename erase_timeout to cmd_timeout_ms.

2011-05-25T01:01:05+00:00

Renames erase_timeout to cmd_timeout_ms inside struct mmc_command.
First step to making host honor timeouts for non-data-transfer
commands. Cleans up erase timeout code.

Signed-off-by: Andrei Warkentin 
Signed-off-by: Chris Ball