linux-sg2042/include/linux/atmel-mci.h

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#ifndef __LINUX_ATMEL_MCI_H
#define __LINUX_ATMEL_MCI_H
atmel-mci: Driver for Atmel on-chip MMC controllers This is a driver for the MMC controller on the AP7000 chips from Atmel. It should in theory work on AT91 systems too with some tweaking, but since the DMA interface is quite different, it's not entirely clear if it's worth merging this with the at91_mci driver. This driver has been around for a while in BSPs and kernel sources provided by Atmel, but this particular version uses the generic DMA Engine framework (with the slave extensions) instead of an avr32-only DMA controller framework. This driver can also use PIO transfers when no DMA channels are available, and for transfers where using DMA may be difficult or impractical for some reason (e.g. the DMA setup overhead is usually not worth it for very short transfers, and badly aligned buffers or lengths are difficult to handle.) Currently, the driver only support PIO transfers. DMA support has been split out to a separate patch to hopefully make it easier to review. The driver has been tested using mmc-block and ext3fs on several SD, SDHC and MMC+ cards. Reads and writes work fine, with read transfer rates up to 3.5 MiB/s on fast cards with debugging disabled. The driver has also been tested using the mmc_test module on the same cards. All tests except 7, 9, 15 and 17 succeed. The first two are unsupported by all the cards I have, so I don't know if the driver handles this correctly. The last two fail because the hardware flags a Data CRC Error instead of a Data Timeout error. I'm not sure how to deal with that. Documentation for this controller can be found in many data sheets from Atmel, including the AT32AP7000 data sheet which can be found here: http://www.atmel.com/dyn/products/datasheets.asp?family_id=682 Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com> Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
2008-07-01 00:35:03 +08:00
#include <linux/types.h>
#include <linux/dmaengine.h>
#define ATMCI_MAX_NR_SLOTS 2
/**
* struct mci_slot_pdata - board-specific per-slot configuration
* @bus_width: Number of data lines wired up the slot
* @detect_pin: GPIO pin wired to the card detect switch
* @wp_pin: GPIO pin wired to the write protect sensor
* @detect_is_active_high: The state of the detect pin when it is active
* @non_removable: The slot is not removable, only detect once
*
* If a given slot is not present on the board, @bus_width should be
* set to 0. The other fields are ignored in this case.
*
* Any pins that aren't available should be set to a negative value.
*
* Note that support for multiple slots is experimental -- some cards
* might get upset if we don't get the clock management exactly right.
* But in most cases, it should work just fine.
*/
struct mci_slot_pdata {
unsigned int bus_width;
atmel-mci: Driver for Atmel on-chip MMC controllers This is a driver for the MMC controller on the AP7000 chips from Atmel. It should in theory work on AT91 systems too with some tweaking, but since the DMA interface is quite different, it's not entirely clear if it's worth merging this with the at91_mci driver. This driver has been around for a while in BSPs and kernel sources provided by Atmel, but this particular version uses the generic DMA Engine framework (with the slave extensions) instead of an avr32-only DMA controller framework. This driver can also use PIO transfers when no DMA channels are available, and for transfers where using DMA may be difficult or impractical for some reason (e.g. the DMA setup overhead is usually not worth it for very short transfers, and badly aligned buffers or lengths are difficult to handle.) Currently, the driver only support PIO transfers. DMA support has been split out to a separate patch to hopefully make it easier to review. The driver has been tested using mmc-block and ext3fs on several SD, SDHC and MMC+ cards. Reads and writes work fine, with read transfer rates up to 3.5 MiB/s on fast cards with debugging disabled. The driver has also been tested using the mmc_test module on the same cards. All tests except 7, 9, 15 and 17 succeed. The first two are unsupported by all the cards I have, so I don't know if the driver handles this correctly. The last two fail because the hardware flags a Data CRC Error instead of a Data Timeout error. I'm not sure how to deal with that. Documentation for this controller can be found in many data sheets from Atmel, including the AT32AP7000 data sheet which can be found here: http://www.atmel.com/dyn/products/datasheets.asp?family_id=682 Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com> Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
2008-07-01 00:35:03 +08:00
int detect_pin;
int wp_pin;
bool detect_is_active_high;
bool non_removable;
atmel-mci: Driver for Atmel on-chip MMC controllers This is a driver for the MMC controller on the AP7000 chips from Atmel. It should in theory work on AT91 systems too with some tweaking, but since the DMA interface is quite different, it's not entirely clear if it's worth merging this with the at91_mci driver. This driver has been around for a while in BSPs and kernel sources provided by Atmel, but this particular version uses the generic DMA Engine framework (with the slave extensions) instead of an avr32-only DMA controller framework. This driver can also use PIO transfers when no DMA channels are available, and for transfers where using DMA may be difficult or impractical for some reason (e.g. the DMA setup overhead is usually not worth it for very short transfers, and badly aligned buffers or lengths are difficult to handle.) Currently, the driver only support PIO transfers. DMA support has been split out to a separate patch to hopefully make it easier to review. The driver has been tested using mmc-block and ext3fs on several SD, SDHC and MMC+ cards. Reads and writes work fine, with read transfer rates up to 3.5 MiB/s on fast cards with debugging disabled. The driver has also been tested using the mmc_test module on the same cards. All tests except 7, 9, 15 and 17 succeed. The first two are unsupported by all the cards I have, so I don't know if the driver handles this correctly. The last two fail because the hardware flags a Data CRC Error instead of a Data Timeout error. I'm not sure how to deal with that. Documentation for this controller can be found in many data sheets from Atmel, including the AT32AP7000 data sheet which can be found here: http://www.atmel.com/dyn/products/datasheets.asp?family_id=682 Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com> Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
2008-07-01 00:35:03 +08:00
};
/**
* struct mci_platform_data - board-specific MMC/SDcard configuration
* @dma_slave: DMA slave interface to use in data transfers.
* @slot: Per-slot configuration data.
*/
struct mci_platform_data {
void *dma_slave;
dma_filter_fn dma_filter;
struct mci_slot_pdata slot[ATMCI_MAX_NR_SLOTS];
};
#endif /* __LINUX_ATMEL_MCI_H */