diff options
Diffstat (limited to 'drivers/mmc/host/at91_mci.c')
| -rw-r--r-- | drivers/mmc/host/at91_mci.c | 1001 |
1 files changed, 1001 insertions, 0 deletions
diff --git a/drivers/mmc/host/at91_mci.c b/drivers/mmc/host/at91_mci.c new file mode 100644 index 00000000000..e37943c314c --- /dev/null +++ b/drivers/mmc/host/at91_mci.c @@ -0,0 +1,1001 @@ +/* + * linux/drivers/mmc/at91_mci.c - ATMEL AT91 MCI Driver + * + * Copyright (C) 2005 Cougar Creek Computing Devices Ltd, All Rights Reserved + * + * Copyright (C) 2006 Malcolm Noyes + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +/* + This is the AT91 MCI driver that has been tested with both MMC cards + and SD-cards. Boards that support write protect are now supported. + The CCAT91SBC001 board does not support SD cards. + + The three entry points are at91_mci_request, at91_mci_set_ios + and at91_mci_get_ro. + + SET IOS + This configures the device to put it into the correct mode and clock speed + required. + + MCI REQUEST + MCI request processes the commands sent in the mmc_request structure. This + can consist of a processing command and a stop command in the case of + multiple block transfers. + + There are three main types of request, commands, reads and writes. + + Commands are straight forward. The command is submitted to the controller and + the request function returns. When the controller generates an interrupt to indicate + the command is finished, the response to the command are read and the mmc_request_done + function called to end the request. + + Reads and writes work in a similar manner to normal commands but involve the PDC (DMA) + controller to manage the transfers. + + A read is done from the controller directly to the scatterlist passed in from the request. + Due to a bug in the AT91RM9200 controller, when a read is completed, all the words are byte + swapped in the scatterlist buffers. AT91SAM926x are not affected by this bug. + + The sequence of read interrupts is: ENDRX, RXBUFF, CMDRDY + + A write is slightly different in that the bytes to write are read from the scatterlist + into a dma memory buffer (this is in case the source buffer should be read only). The + entire write buffer is then done from this single dma memory buffer. + + The sequence of write interrupts is: ENDTX, TXBUFE, NOTBUSY, CMDRDY + + GET RO + Gets the status of the write protect pin, if available. +*/ + +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/init.h> +#include <linux/ioport.h> +#include <linux/platform_device.h> +#include <linux/interrupt.h> +#include <linux/blkdev.h> +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/dma-mapping.h> +#include <linux/clk.h> +#include <linux/atmel_pdc.h> + +#include <linux/mmc/host.h> + +#include <asm/io.h> +#include <asm/irq.h> +#include <asm/mach/mmc.h> +#include <asm/arch/board.h> +#include <asm/arch/cpu.h> +#include <asm/arch/gpio.h> +#include <asm/arch/at91_mci.h> + +#define DRIVER_NAME "at91_mci" + +#undef SUPPORT_4WIRE + +#define FL_SENT_COMMAND (1 << 0) +#define FL_SENT_STOP (1 << 1) + +#define AT91_MCI_ERRORS (AT91_MCI_RINDE | AT91_MCI_RDIRE | AT91_MCI_RCRCE \ + | AT91_MCI_RENDE | AT91_MCI_RTOE | AT91_MCI_DCRCE \ + | AT91_MCI_DTOE | AT91_MCI_OVRE | AT91_MCI_UNRE) + +#define at91_mci_read(host, reg) __raw_readl((host)->baseaddr + (reg)) +#define at91_mci_write(host, reg, val) __raw_writel((val), (host)->baseaddr + (reg)) + + +/* + * Low level type for this driver + */ +struct at91mci_host +{ + struct mmc_host *mmc; + struct mmc_command *cmd; + struct mmc_request *request; + + void __iomem *baseaddr; + int irq; + + struct at91_mmc_data *board; + int present; + + struct clk *mci_clk; + + /* + * Flag indicating when the command has been sent. This is used to + * work out whether or not to send the stop + */ + unsigned int flags; + /* flag for current bus settings */ + u32 bus_mode; + + /* DMA buffer used for transmitting */ + unsigned int* buffer; + dma_addr_t physical_address; + unsigned int total_length; + + /* Latest in the scatterlist that has been enabled for transfer, but not freed */ + int in_use_index; + + /* Latest in the scatterlist that has been enabled for transfer */ + int transfer_index; +}; + +/* + * Copy from sg to a dma block - used for transfers + */ +static inline void at91mci_sg_to_dma(struct at91mci_host *host, struct mmc_data *data) +{ + unsigned int len, i, size; + unsigned *dmabuf = host->buffer; + + size = host->total_length; + len = data->sg_len; + + /* + * Just loop through all entries. Size might not + * be the entire list though so make sure that + * we do not transfer too much. + */ + for (i = 0; i < len; i++) { + struct scatterlist *sg; + int amount; + unsigned int *sgbuffer; + + sg = &data->sg[i]; + + sgbuffer = kmap_atomic(sg->page, KM_BIO_SRC_IRQ) + sg->offset; + amount = min(size, sg->length); + size -= amount; + + if (cpu_is_at91rm9200()) { /* AT91RM9200 errata */ + int index; + + for (index = 0; index < (amount / 4); index++) + *dmabuf++ = swab32(sgbuffer[index]); + } + else + memcpy(dmabuf, sgbuffer, amount); + + kunmap_atomic(sgbuffer, KM_BIO_SRC_IRQ); + + if (size == 0) + break; + } + + /* + * Check that we didn't get a request to transfer + * more data than can fit into the SG list. + */ + BUG_ON(size != 0); +} + +/* + * Prepare a dma read + */ +static void at91mci_pre_dma_read(struct at91mci_host *host) +{ + int i; + struct scatterlist *sg; + struct mmc_command *cmd; + struct mmc_data *data; + + pr_debug("pre dma read\n"); + + cmd = host->cmd; + if (!cmd) { + pr_debug("no command\n"); + return; + } + + data = cmd->data; + if (!data) { + pr_debug("no data\n"); + return; + } + + for (i = 0; i < 2; i++) { + /* nothing left to transfer */ + if (host->transfer_index >= data->sg_len) { + pr_debug("Nothing left to transfer (index = %d)\n", host->transfer_index); + break; + } + + /* Check to see if this needs filling */ + if (i == 0) { + if (at91_mci_read(host, ATMEL_PDC_RCR) != 0) { + pr_debug("Transfer active in current\n"); + continue; + } + } + else { + if (at91_mci_read(host, ATMEL_PDC_RNCR) != 0) { + pr_debug("Transfer active in next\n"); + continue; + } + } + + /* Setup the next transfer */ + pr_debug("Using transfer index %d\n", host->transfer_index); + + sg = &data->sg[host->transfer_index++]; + pr_debug("sg = %p\n", sg); + + sg->dma_address = dma_map_page(NULL, sg->page, sg->offset, sg->length, DMA_FROM_DEVICE); + + pr_debug("dma address = %08X, length = %d\n", sg->dma_address, sg->length); + + if (i == 0) { + at91_mci_write(host, ATMEL_PDC_RPR, sg->dma_address); + at91_mci_write(host, ATMEL_PDC_RCR, sg->length / 4); + } + else { + at91_mci_write(host, ATMEL_PDC_RNPR, sg->dma_address); + at91_mci_write(host, ATMEL_PDC_RNCR, sg->length / 4); + } + } + + pr_debug("pre dma read done\n"); +} + +/* + * Handle after a dma read + */ +static void at91mci_post_dma_read(struct at91mci_host *host) +{ + struct mmc_command *cmd; + struct mmc_data *data; + + pr_debug("post dma read\n"); + + cmd = host->cmd; + if (!cmd) { + pr_debug("no command\n"); + return; + } + + data = cmd->data; + if (!data) { + pr_debug("no data\n"); + return; + } + + while (host->in_use_index < host->transfer_index) { + unsigned int *buffer; + + struct scatterlist *sg; + + pr_debug("finishing index %d\n", host->in_use_index); + + sg = &data->sg[host->in_use_index++]; + + pr_debug("Unmapping page %08X\n", sg->dma_address); + + dma_unmap_page(NULL, sg->dma_address, sg->length, DMA_FROM_DEVICE); + + /* Swap the contents of the buffer */ + buffer = kmap_atomic(sg->page, KM_BIO_SRC_IRQ) + sg->offset; + pr_debug("buffer = %p, length = %d\n", buffer, sg->length); + + data->bytes_xfered += sg->length; + + if (cpu_is_at91rm9200()) { /* AT91RM9200 errata */ + int index; + + for (index = 0; index < (sg->length / 4); index++) + buffer[index] = swab32(buffer[index]); + } + + kunmap_atomic(buffer, KM_BIO_SRC_IRQ); + flush_dcache_page(sg->page); + } + + /* Is there another transfer to trigger? */ + if (host->transfer_index < data->sg_len) + at91mci_pre_dma_read(host); + else { + at91_mci_write(host, AT91_MCI_IER, AT91_MCI_RXBUFF); + at91_mci_write(host, ATMEL_PDC_PTCR, ATMEL_PDC_RXTDIS | ATMEL_PDC_TXTDIS); + } + + pr_debug("post dma read done\n"); +} + +/* + * Handle transmitted data + */ +static void at91_mci_handle_transmitted(struct at91mci_host *host) +{ + struct mmc_command *cmd; + struct mmc_data *data; + + pr_debug("Handling the transmit\n"); + + /* Disable the transfer */ + at91_mci_write(host, ATMEL_PDC_PTCR, ATMEL_PDC_RXTDIS | ATMEL_PDC_TXTDIS); + + /* Now wait for cmd ready */ + at91_mci_write(host, AT91_MCI_IDR, AT91_MCI_TXBUFE); + at91_mci_write(host, AT91_MCI_IER, AT91_MCI_NOTBUSY); + + cmd = host->cmd; + if (!cmd) return; + + data = cmd->data; + if (!data) return; + + data->bytes_xfered = host->total_length; +} + +/* + * Enable the controller + */ +static void at91_mci_enable(struct at91mci_host *host) +{ + at91_mci_write(host, AT91_MCI_CR, AT91_MCI_MCIEN); + at91_mci_write(host, AT91_MCI_IDR, 0xffffffff); + at91_mci_write(host, AT91_MCI_DTOR, AT91_MCI_DTOMUL_1M | AT91_MCI_DTOCYC); + at91_mci_write(host, AT91_MCI_MR, AT91_MCI_PDCMODE | 0x34a); + + /* use Slot A or B (only one at same time) */ + at91_mci_write(host, AT91_MCI_SDCR, host->board->slot_b); +} + +/* + * Disable the controller + */ +static void at91_mci_disable(struct at91mci_host *host) +{ + at91_mci_write(host, AT91_MCI_CR, AT91_MCI_MCIDIS | AT91_MCI_SWRST); +} + +/* + * Send a command + * return the interrupts to enable + */ +static unsigned int at91_mci_send_command(struct at91mci_host *host, struct mmc_command *cmd) +{ + unsigned int cmdr, mr; + unsigned int block_length; + struct mmc_data *data = cmd->data; + + unsigned int blocks; + unsigned int ier = 0; + + host->cmd = cmd; + + /* Not sure if this is needed */ +#if 0 + if ((at91_mci_read(host, AT91_MCI_SR) & AT91_MCI_RTOE) && (cmd->opcode == 1)) { + pr_debug("Clearing timeout\n"); + at91_mci_write(host, AT91_MCI_ARGR, 0); + at91_mci_write(host, AT91_MCI_CMDR, AT91_MCI_OPDCMD); + while (!(at91_mci_read(host, AT91_MCI_SR) & AT91_MCI_CMDRDY)) { + /* spin */ + pr_debug("Clearing: SR = %08X\n", at91_mci_read(host, AT91_MCI_SR)); + } + } +#endif + cmdr = cmd->opcode; + + if (mmc_resp_type(cmd) == MMC_RSP_NONE) + cmdr |= AT91_MCI_RSPTYP_NONE; + else { + /* if a response is expected then allow maximum response latancy */ + cmdr |= AT91_MCI_MAXLAT; + /* set 136 bit response for R2, 48 bit response otherwise */ + if (mmc_resp_type(cmd) == MMC_RSP_R2) + cmdr |= AT91_MCI_RSPTYP_136; + else + cmdr |= AT91_MCI_RSPTYP_48; + } + + if (data) { + block_length = data->blksz; + blocks = data->blocks; + + /* always set data start - also set direction flag for read */ + if (data->flags & MMC_DATA_READ) + cmdr |= (AT91_MCI_TRDIR | AT91_MCI_TRCMD_START); + else if (data->flags & MMC_DATA_WRITE) + cmdr |= AT91_MCI_TRCMD_START; + + if (data->flags & MMC_DATA_STREAM) + cmdr |= AT91_MCI_TRTYP_STREAM; + if (data->flags & MMC_DATA_MULTI) + cmdr |= AT91_MCI_TRTYP_MULTIPLE; + } + else { + block_length = 0; + blocks = 0; + } + + if (cmd->opcode == MMC_STOP_TRANSMISSION) + cmdr |= AT91_MCI_TRCMD_STOP; + + if (host->bus_mode == MMC_BUSMODE_OPENDRAIN) + cmdr |= AT91_MCI_OPDCMD; + + /* + * Set the arguments and send the command + */ + pr_debug("Sending command %d as %08X, arg = %08X, blocks = %d, length = %d (MR = %08X)\n", + cmd->opcode, cmdr, cmd->arg, blocks, block_length, at91_mci_read(host, AT91_MCI_MR)); + + if (!data) { + at91_mci_write(host, ATMEL_PDC_PTCR, ATMEL_PDC_TXTDIS | ATMEL_PDC_RXTDIS); + at91_mci_write(host, ATMEL_PDC_RPR, 0); + at91_mci_write(host, ATMEL_PDC_RCR, 0); + at91_mci_write(host, ATMEL_PDC_RNPR, 0); + at91_mci_write(host, ATMEL_PDC_RNCR, 0); + at91_mci_write(host, ATMEL_PDC_TPR, 0); + at91_mci_write(host, ATMEL_PDC_TCR, 0); + at91_mci_write(host, ATMEL_PDC_TNPR, 0); + at91_mci_write(host, ATMEL_PDC_TNCR, 0); + + at91_mci_write(host, AT91_MCI_ARGR, cmd->arg); + at91_mci_write(host, AT91_MCI_CMDR, cmdr); + return AT91_MCI_CMDRDY; + } + + mr = at91_mci_read(host, AT91_MCI_MR) & 0x7fff; /* zero block length and PDC mode */ + at91_mci_write(host, AT91_MCI_MR, mr | (block_length << 16) | AT91_MCI_PDCMODE); + + /* + * Disable the PDC controller + */ + at91_mci_write(host, ATMEL_PDC_PTCR, ATMEL_PDC_RXTDIS | ATMEL_PDC_TXTDIS); + + if (cmdr & AT91_MCI_TRCMD_START) { + data->bytes_xfered = 0; + host->transfer_index = 0; + host->in_use_index = 0; + if (cmdr & AT91_MCI_TRDIR) { + /* + * Handle a read + */ + host->buffer = NULL; + host->total_length = 0; + + at91mci_pre_dma_read(host); + ier = AT91_MCI_ENDRX /* | AT91_MCI_RXBUFF */; + } + else { + /* + * Handle a write + */ + host->total_length = block_length * blocks; + host->buffer = dma_alloc_coherent(NULL, + host->total_length, + &host->physical_address, GFP_KERNEL); + + at91mci_sg_to_dma(host, data); + + pr_debug("Transmitting %d bytes\n", host->total_length); + + at91_mci_write(host, ATMEL_PDC_TPR, host->physical_address); + at91_mci_write(host, ATMEL_PDC_TCR, host->total_length / 4); + ier = AT91_MCI_TXBUFE; + } + } + + /* + * Send the command and then enable the PDC - not the other way round as + * the data sheet says + */ + + at91_mci_write(host, AT91_MCI_ARGR, cmd->arg); + at91_mci_write(host, AT91_MCI_CMDR, cmdr); + + if (cmdr & AT91_MCI_TRCMD_START) { + if (cmdr & AT91_MCI_TRDIR) + at91_mci_write(host, ATMEL_PDC_PTCR, ATMEL_PDC_RXTEN); + else + at91_mci_write(host, ATMEL_PDC_PTCR, ATMEL_PDC_TXTEN); + } + return ier; +} + +/* + * Wait for a command to complete + */ +static void at91mci_process_command(struct at91mci_host *host, struct mmc_command *cmd) +{ + unsigned int ier; + + ier = at91_mci_send_command(host, cmd); + + pr_debug("setting ier to %08X\n", ier); + + /* Stop on errors or the required value */ + at91_mci_write(host, AT91_MCI_IER, AT91_MCI_ERRORS | ier); +} + +/* + * Process the next step in the request + */ +static void at91mci_process_next(struct at91mci_host *host) +{ + if (!(host->flags & FL_SENT_COMMAND)) { + host->flags |= FL_SENT_COMMAND; + at91mci_process_command(host, host->request->cmd); + } + else if ((!(host->flags & FL_SENT_STOP)) && host->request->stop) { + host->flags |= FL_SENT_STOP; + at91mci_process_command(host, host->request->stop); + } + else + mmc_request_done(host->mmc, host->request); +} + +/* + * Handle a command that has been completed + */ +static void at91mci_completed_command(struct at91mci_host *host) +{ + struct mmc_command *cmd = host->cmd; + unsigned int status; + + at91_mci_write(host, AT91_MCI_IDR, 0xffffffff); + + cmd->resp[0] = at91_mci_read(host, AT91_MCI_RSPR(0)); + cmd->resp[1] = at91_mci_read(host, AT91_MCI_RSPR(1)); + cmd->resp[2] = at91_mci_read(host, AT91_MCI_RSPR(2)); + cmd->resp[3] = at91_mci_read(host, AT91_MCI_RSPR(3)); + + if (host->buffer) { + dma_free_coherent(NULL, host->total_length, host->buffer, host->physical_address); + host->buffer = NULL; + } + + status = at91_mci_read(host, AT91_MCI_SR); + + pr_debug("Status = %08X [%08X %08X %08X %08X]\n", + status, cmd->resp[0], cmd->resp[1], cmd->resp[2], cmd->resp[3]); + + if (status & (AT91_MCI_RINDE | AT91_MCI_RDIRE | AT91_MCI_RCRCE | + AT91_MCI_RENDE | AT91_MCI_RTOE | AT91_MCI_DCRCE | + AT91_MCI_DTOE | AT91_MCI_OVRE | AT91_MCI_UNRE)) { + if ((status & AT91_MCI_RCRCE) && + ((cmd->opcode == MMC_SEND_OP_COND) || (cmd->opcode == SD_APP_OP_COND))) { + cmd->error = MMC_ERR_NONE; + } + else { + if (status & (AT91_MCI_RTOE | AT91_MCI_DTOE)) + cmd->error = MMC_ERR_TIMEOUT; + else if (status & (AT91_MCI_RCRCE | AT91_MCI_DCRCE)) + cmd->error = MMC_ERR_BADCRC; + else if (status & (AT91_MCI_OVRE | AT91_MCI_UNRE)) + cmd->error = MMC_ERR_FIFO; + else + cmd->error = MMC_ERR_FAILED; + + pr_debug("Error detected and set to %d (cmd = %d, retries = %d)\n", + cmd->error, cmd->opcode, cmd->retries); + } + } + else + cmd->error = MMC_ERR_NONE; + + at91mci_process_next(host); +} + +/* + * Handle an MMC request + */ +static void at91_mci_request(struct mmc_host *mmc, struct mmc_request *mrq) +{ + struct at91mci_host *host = mmc_priv(mmc); + host->request = mrq; + host->flags = 0; + + at91mci_process_next(host); +} + +/* + * Set the IOS + */ +static void at91_mci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) +{ + int clkdiv; + struct at91mci_host *host = mmc_priv(mmc); + unsigned long at91_master_clock = clk_get_rate(host->mci_clk); + + host->bus_mode = ios->bus_mode; + + if (ios->clock == 0) { + /* Disable the MCI controller */ + at91_mci_write(host, AT91_MCI_CR, AT91_MCI_MCIDIS); + clkdiv = 0; + } + else { + /* Enable the MCI controller */ + at91_mci_write(host, AT91_MCI_CR, AT91_MCI_MCIEN); + + if ((at91_master_clock % (ios->clock * 2)) == 0) + clkdiv = ((at91_master_clock / ios->clock) / 2) - 1; + else + clkdiv = (at91_master_clock / ios->clock) / 2; + + pr_debug("clkdiv = %d. mcck = %ld\n", clkdiv, + at91_master_clock / (2 * (clkdiv + 1))); + } + if (ios->bus_width == MMC_BUS_WIDTH_4 && host->board->wire4) { + pr_debug("MMC: Setting controller bus width to 4\n"); + at91_mci_write(host, AT91_MCI_SDCR, at91_mci_read(host, AT91_MCI_SDCR) | AT91_MCI_SDCBUS); + } + else { + pr_debug("MMC: Setting controller bus width to 1\n"); + at91_mci_write(host, AT91_MCI_SDCR, at91_mci_read(host, AT91_MCI_SDCR) & ~AT91_MCI_SDCBUS); + } + + /* Set the clock divider */ + at91_mci_write(host, AT91_MCI_MR, (at91_mci_read(host, AT91_MCI_MR) & ~AT91_MCI_CLKDIV) | clkdiv); + + /* maybe switch power to the card */ + if (host->board->vcc_pin) { + switch (ios->power_mode) { + case MMC_POWER_OFF: + at91_set_gpio_value(host->board->vcc_pin, 0); + break; + case MMC_POWER_UP: + case MMC_POWER_ON: + at91_set_gpio_value(host->board->vcc_pin, 1); + break; + } + } +} + +/* + * Handle an interrupt + */ +static irqreturn_t at91_mci_irq(int irq, void *devid) +{ + struct at91mci_host *host = devid; + int completed = 0; + unsigned int int_status, int_mask; + + int_status = at91_mci_read(host, AT91_MCI_SR); + int_mask = at91_mci_read(host, AT91_MCI_IMR); + + pr_debug("MCI irq: status = %08X, %08X, %08X\n", int_status, int_mask, + int_status & int_mask); + + int_status = int_status & int_mask; + + if (int_status & AT91_MCI_ERRORS) { + completed = 1; + + if (int_status & AT91_MCI_UNRE) + pr_debug("MMC: Underrun error\n"); + if (int_status & AT91_MCI_OVRE) + pr_debug("MMC: Overrun error\n"); + if (int_status & AT91_MCI_DTOE) + pr_debug("MMC: Data timeout\n"); + if (int_status & AT91_MCI_DCRCE) + pr_debug("MMC: CRC error in data\n"); + if (int_status & AT91_MCI_RTOE) + pr_debug("MMC: Response timeout\n"); + if (int_status & AT91_MCI_RENDE) + pr_debug("MMC: Response end bit error\n"); + if (int_status & AT91_MCI_RCRCE) + pr_debug("MMC: Response CRC error\n"); + if (int_status & AT91_MCI_RDIRE) + pr_debug("MMC: Response direction error\n"); + if (int_status & AT91_MCI_RINDE) + pr_debug("MMC: Response index error\n"); + } else { + /* Only continue processing if no errors */ + + if (int_status & AT91_MCI_TXBUFE) { + pr_debug("TX buffer empty\n"); + at91_mci_handle_transmitted(host); + } + + if (int_status & AT91_MCI_RXBUFF) { + pr_debug("RX buffer full\n"); + at91_mci_write(host, AT91_MCI_IER, AT91_MCI_CMDRDY); + } + + if (int_status & AT91_MCI_ENDTX) + pr_debug("Transmit has ended\n"); + + if (int_status & AT91_MCI_ENDRX) { + pr_debug("Receive has ended\n"); + at91mci_post_dma_read(host); + } + + if (int_status & AT91_MCI_NOTBUSY) { + pr_debug("Card is ready\n"); + at91_mci_write(host, AT91_MCI_IER, AT91_MCI_CMDRDY); + } + + if (int_status & AT91_MCI_DTIP) + pr_debug("Data transfer in progress\n"); + + if (int_status & AT91_MCI_BLKE) + pr_debug("Block transfer has ended\n"); + + if (int_status & AT91_MCI_TXRDY) + pr_debug("Ready to transmit\n"); + + if (int_status & AT91_MCI_RXRDY) + pr_debug("Ready to receive\n"); + + if (int_status & AT91_MCI_CMDRDY) { + pr_debug("Command ready\n"); + completed = 1; + } + } + + if (completed) { + pr_debug("Completed command\n"); + at91_mci_write(host, AT91_MCI_IDR, 0xffffffff); + at91mci_completed_command(host); + } else + at91_mci_write(host, AT91_MCI_IDR, int_status); + + return IRQ_HANDLED; +} + +static irqreturn_t at91_mmc_det_irq(int irq, void *_host) +{ + struct at91mci_host *host = _host; + int present = !at91_get_gpio_value(irq); + + /* + * we expect this irq on both insert and remove, + * and use a short delay to debounce. + */ + if (present != host->present) { + host->present = present; + pr_debug("%s: card %s\n", mmc_hostname(host->mmc), + present ? "insert" : "remove"); + if (!present) { + pr_debug("****** Resetting SD-card bus width ******\n"); + at91_mci_write(host, AT91_MCI_SDCR, at91_mci_read(host, AT91_MCI_SDCR) & ~AT91_MCI_SDCBUS); + } + mmc_detect_change(host->mmc, msecs_to_jiffies(100)); + } + return IRQ_HANDLED; +} + +static int at91_mci_get_ro(struct mmc_host *mmc) +{ + int read_only = 0; + struct at91mci_host *host = mmc_priv(mmc); + + if (host->board->wp_pin) { + read_only = at91_get_gpio_value(host->board->wp_pin); + printk(KERN_WARNING "%s: card is %s\n", mmc_hostname(mmc), + (read_only ? "read-only" : "read-write") ); + } + else { + printk(KERN_WARNING "%s: host does not support reading read-only " + "switch. Assuming write-enable.\n", mmc_hostname(mmc)); + } + return read_only; +} + +static const struct mmc_host_ops at91_mci_ops = { + .request = at91_mci_request, + .set_ios = at91_mci_set_ios, + .get_ro = at91_mci_get_ro, +}; + +/* + * Probe for the device + */ +static int __init at91_mci_probe(struct platform_device *pdev) +{ + struct mmc_host *mmc; + struct at91mci_host *host; + struct resource *res; + int ret; + + pr_debug("Probe MCI devices\n"); + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) + return -ENXIO; + + if (!request_mem_region(res->start, res->end - res->start + 1, DRIVER_NAME)) + return -EBUSY; + + mmc = mmc_alloc_host(sizeof(struct at91mci_host), &pdev->dev); + if (!mmc) { + pr_debug("Failed to allocate mmc host\n"); + release_mem_region(res->start, res->end - res->start + 1); + return -ENOMEM; + } + + mmc->ops = &at91_mci_ops; + mmc->f_min = 375000; + mmc->f_max = 25000000; + mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34; + mmc->caps = MMC_CAP_BYTEBLOCK; + + mmc->max_blk_size = 4095; + mmc->max_blk_count = mmc->max_req_size; + + host = mmc_priv(mmc); + host->mmc = mmc; + host->buffer = NULL; + host->bus_mode = 0; + host->board = pdev->dev.platform_data; + if (host->board->wire4) { +#ifdef SUPPORT_4WIRE + mmc->caps |= MMC_CAP_4_BIT_DATA; +#else + printk("AT91 MMC: 4 wire bus mode not supported by this driver - using 1 wire\n"); +#endif + } + + /* + * Get Clock + */ + host->mci_clk = clk_get(&pdev->dev, "mci_clk"); + if (IS_ERR(host->mci_clk)) { + printk(KERN_ERR "AT91 MMC: no clock defined.\n"); + mmc_free_host(mmc); + release_mem_region(res->start, res->end - res->start + 1); + return -ENODEV; + } + + /* + * Map I/O region + */ + host->baseaddr = ioremap(res->start, res->end - res->start + 1); + if (!host->baseaddr) { + clk_put(host->mci_clk); + mmc_free_host(mmc); + release_mem_region(res->start, res->end - res->start + 1); + return -ENOMEM; + } + + /* + * Reset hardware + */ + clk_enable(host->mci_clk); /* Enable the peripheral clock */ + at91_mci_disable(host); + at91_mci_enable(host); + + /* + * Allocate the MCI interrupt + */ + host->irq = platform_get_irq(pdev, 0); + ret = request_irq(host->irq, at91_mci_irq, IRQF_SHARED, DRIVER_NAME, host); + if (ret) { + printk(KERN_ERR "AT91 MMC: Failed to request MCI interrupt\n"); + clk_disable(host->mci_clk); + clk_put(host->mci_clk); + mmc_free_host(mmc); + iounmap(host->baseaddr); + release_mem_region(res->start, res->end - res->start + 1); + return ret; + } + + platform_set_drvdata(pdev, mmc); + + /* + * Add host to MMC layer + */ + if (host->board->det_pin) + host->present = !at91_get_gpio_value(host->board->det_pin); + else + host->present = -1; + + mmc_add_host(mmc); + + /* + * monitor card insertion/removal if we can + */ + if (host->board->det_pin) { + ret = request_irq(host->board->det_pin, at91_mmc_det_irq, + 0, DRIVER_NAME, host); + if (ret) + printk(KERN_ERR "AT91 MMC: Couldn't allocate MMC detect irq\n"); + } + + pr_debug("Added MCI driver\n"); + + return 0; +} + +/* + * Remove a device + */ +static int __exit at91_mci_remove(struct platform_device *pdev) +{ + struct mmc_host *mmc = platform_get_drvdata(pdev); + struct at91mci_host *host; + struct resource *res; + + if (!mmc) + return -1; + + host = mmc_priv(mmc); + + if (host->present != -1) { + free_irq(host->board->det_pin, host); + cancel_delayed_work(&host->mmc->detect); + } + + at91_mci_disable(host); + mmc_remove_host(mmc); + free_irq(host->irq, host); + + clk_disable(host->mci_clk); /* Disable the peripheral clock */ + clk_put(host->mci_clk); + + iounmap(host->baseaddr); + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + release_mem_region(res->start, res->end - res->start + 1); + + mmc_free_host(mmc); + platform_set_drvdata(pdev, NULL); + pr_debug("MCI Removed\n"); + + return 0; +} + +#ifdef CONFIG_PM +static int at91_mci_suspend(struct platform_device *pdev, pm_message_t state) +{ + struct mmc_host *mmc = platform_get_drvdata(pdev); + int ret = 0; + + if (mmc) + ret = mmc_suspend_host(mmc, state); + + return ret; +} + +static int at91_mci_resume(struct platform_device *pdev) +{ + struct mmc_host *mmc = platform_get_drvdata(pdev); + int ret = 0; + + if (mmc) + ret = mmc_resume_host(mmc); + + return ret; +} +#else +#define at91_mci_suspend NULL +#define at91_mci_resume NULL +#endif + +static struct platform_driver at91_mci_driver = { + .remove = __exit_p(at91_mci_remove), + .suspend = at91_mci_suspend, + .resume = at91_mci_resume, + .driver = { + .name = DRIVER_NAME, + .owner = THIS_MODULE, + }, +}; + +static int __init at91_mci_init(void) +{ + return platform_driver_probe(&at91_mci_driver, at91_mci_probe); +} + +static void __exit at91_mci_exit(void) +{ + platform_driver_unregister(&at91_mci_driver); +} + +module_init(at91_mci_init); +module_exit(at91_mci_exit); + +MODULE_DESCRIPTION("AT91 Multimedia Card Interface driver"); +MODULE_AUTHOR("Nick Randell"); +MODULE_LICENSE("GPL"); |