kernel.git/drivers/mmc/core/core.h, branch linux-3.2.y

mmc: core: Fix hangs related to insert/remove of cards

2011-10-26T20:32:01Z

During a rescan operation mmc_attach(sd|mmc|sdio) functions are called. The error handling in these function can trigger a detach of the bus, which also meant a power off. This is not notified by the rescan operation which then continues to the next attach function. If a power off has been done, the framework must never send any new commands to the host driver, without first doing a new power up. This will most likely trigger any host driver to hang. Moving power off out of detach and instead handle power off separately when it is actually needed, solves the issue. Signed-off-by: Ulf Hansson Acked-by: Linus Walleij Cc: Signed-off-by: Chris Ball

mmc: core: add support for eMMC Dual Data Rate

2011-05-25T03:53:58Z

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

2011-05-25T03:53:58Z

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: sd: add support for driver type selection

2011-05-25T03:53:24Z

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

2011-05-25T01:04:38Z

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: quirks: Extends card quirks with MMC/SD quirks matching the CID.

2011-05-25T01:00:54Z

The current mechanism is SDIO-only. This allows us to create function-specific quirks, without creating messy Kconfig dependencies, or polluting core/ with function-specific code. Signed-off-by: Andrei Warkentin Acked-by: Arnd Bergmann Signed-off-by: Chris Ball

mmc: add per device quirk placeholder

2011-03-15T17:48:33Z

Some cards have quirks valid for every platforms using current platform quirk hooks leads to a lot of code and debug duplication. So we inspire a bit from what exists in PCI subsystem and do our own per vendorid/deviceid quirk. We still drop the complexity of the pci quirk system (with special section tables, and so on). That can be added later if needed. Signed-off-by: Pierre Tardy Acked-by: Linus Walleij Acked-by: Ohad Ben-Cohen Signed-off-by: Chris Ball

mmc: Fix sd/sdio/mmc initialization frequency retries

2011-01-09T04:52:25Z

Rewrite and clean up mmc_rescan() to properly retry frequencies lower than 400kHz. Failures can happen both in sd_send_* calls and mmc_attach_*. Break out "mmc_rescan_try_freq" from the frequency selection loop. Symmetrize claim/release logic in mmc_attach_* API, and move the sd_send_* calls there to make mmc_rescan easier to read. Signed-off-by: Andy Ross Reviewed-and-Tested-by: Hein Tibosch Reviewed-by: Chris Ball Signed-off-by: Chris Ball

mmc: Aggressive clock gating framework

2011-01-09T03:48:03Z

This patch modifies the MMC core code to optionally call the set_ios() operation on the driver with the clock frequency set to 0 (gate) after a grace period of at least 8 MCLK cycles, then restore it (ungate) before any new request. This gives the driver the option to shut down the MCI clock to the MMC/SD card when the clock frequency is 0, i.e. the core has stated that the MCI clock does not need to be generated. It is inspired by existing clock gating code found in the OMAP and Atmel drivers and brings this up to the host abstraction. Gating is performed before and after any MMC request. This patchset implements this for the MMCI/PL180 MMC/SD host controller, but it should be simple to switch OMAP/Atmel over to using this instead. mmc_set_{gated,ungated}() add variable protection to the state holders for the clock gating code. This is particularly important when ordinary .set_ios() calls would race with the .set_ios() call resulting from a delayed gate operation. Signed-off-by: Linus Walleij Reviewed-by: Chris Ball Tested-by: Chris Ball Signed-off-by: Chris Ball

mmc: propagate power save/restore ops return value

2010-10-23T13:11:17Z

Allow power save/restore and their relevant mmc_bus_ops handlers exit with a return value. Signed-off-by: Ohad Ben-Cohen Tested-by: Luciano Coelho Signed-off-by: Chris Ball