diff options
Diffstat (limited to 'drivers/net/wireless/libertas/if_spi.c')
| -rw-r--r-- | drivers/net/wireless/libertas/if_spi.c | 1203 |
1 files changed, 1203 insertions, 0 deletions
diff --git a/drivers/net/wireless/libertas/if_spi.c b/drivers/net/wireless/libertas/if_spi.c new file mode 100644 index 0000000..7c02ea3 --- /dev/null +++ b/drivers/net/wireless/libertas/if_spi.c @@ -0,0 +1,1203 @@ +/* + * linux/drivers/net/wireless/libertas/if_spi.c + * + * Driver for Marvell SPI WLAN cards. + * + * Copyright 2008 Analog Devices Inc. + * + * Authors: + * Andrey Yurovsky <andrey@cozybit.com> + * Colin McCabe <colin@cozybit.com> + * + * Inspired by if_sdio.c, Copyright 2007-2008 Pierre Ossman + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + */ + +#include <linux/moduleparam.h> +#include <linux/firmware.h> +#include <linux/gpio.h> +#include <linux/jiffies.h> +#include <linux/kthread.h> +#include <linux/list.h> +#include <linux/netdevice.h> +#include <linux/spi/libertas_spi.h> +#include <linux/spi/spi.h> + +#include "host.h" +#include "decl.h" +#include "defs.h" +#include "dev.h" +#include "if_spi.h" + +struct if_spi_packet { + struct list_head list; + u16 blen; + u8 buffer[0] __attribute__((aligned(4))); +}; + +struct if_spi_card { + struct spi_device *spi; + struct lbs_private *priv; + + char helper_fw_name[FIRMWARE_NAME_MAX]; + char main_fw_name[FIRMWARE_NAME_MAX]; + + /* The card ID and card revision, as reported by the hardware. */ + u16 card_id; + u8 card_rev; + + /* Pin number for our GPIO chip-select. */ + /* TODO: Once the generic SPI layer has some additional features, we + * should take this out and use the normal chip select here. + * We need support for chip select delays, and not dropping chipselect + * after each word. */ + int gpio_cs; + + /* The last time that we initiated an SPU operation */ + unsigned long prev_xfer_time; + + int use_dummy_writes; + unsigned long spu_port_delay; + unsigned long spu_reg_delay; + + /* Handles all SPI communication (except for FW load) */ + struct task_struct *spi_thread; + int run_thread; + + /* Used to wake up the spi_thread */ + struct semaphore spi_ready; + struct semaphore spi_thread_terminated; + + u8 cmd_buffer[IF_SPI_CMD_BUF_SIZE]; + + /* A buffer of incoming packets from libertas core. + * Since we can't sleep in hw_host_to_card, we have to buffer + * them. */ + struct list_head cmd_packet_list; + struct list_head data_packet_list; + + /* Protects cmd_packet_list and data_packet_list */ + spinlock_t buffer_lock; +}; + +static void free_if_spi_card(struct if_spi_card *card) +{ + struct list_head *cursor, *next; + struct if_spi_packet *packet; + + BUG_ON(card->run_thread); + list_for_each_safe(cursor, next, &card->cmd_packet_list) { + packet = container_of(cursor, struct if_spi_packet, list); + list_del(&packet->list); + kfree(packet); + } + list_for_each_safe(cursor, next, &card->data_packet_list) { + packet = container_of(cursor, struct if_spi_packet, list); + list_del(&packet->list); + kfree(packet); + } + spi_set_drvdata(card->spi, NULL); + kfree(card); +} + +static struct chip_ident chip_id_to_device_name[] = { + { .chip_id = 0x04, .name = 8385 }, + { .chip_id = 0x0b, .name = 8686 }, +}; + +/* + * SPI Interface Unit Routines + * + * The SPU sits between the host and the WLAN module. + * All communication with the firmware is through SPU transactions. + * + * First we have to put a SPU register name on the bus. Then we can + * either read from or write to that register. + * + * For 16-bit transactions, byte order on the bus is big-endian. + * We don't have to worry about that here, though. + * The translation takes place in the SPI routines. + */ + +static void spu_transaction_init(struct if_spi_card *card) +{ + if (!time_after(jiffies, card->prev_xfer_time + 1)) { + /* Unfortunately, the SPU requires a delay between successive + * transactions. If our last transaction was more than a jiffy + * ago, we have obviously already delayed enough. + * If not, we have to busy-wait to be on the safe side. */ + ndelay(400); + } + gpio_set_value(card->gpio_cs, 0); /* assert CS */ +} + +static void spu_transaction_finish(struct if_spi_card *card) +{ + gpio_set_value(card->gpio_cs, 1); /* drop CS */ + card->prev_xfer_time = jiffies; +} + +/* Write out a byte buffer to an SPI register, + * using a series of 16-bit transfers. */ +static int spu_write(struct if_spi_card *card, u16 reg, const u8 *buf, int len) +{ + int err = 0; + u16 reg_out = reg | IF_SPI_WRITE_OPERATION_MASK; + + /* You must give an even number of bytes to the SPU, even if it + * doesn't care about the last one. */ + BUG_ON(len & 0x1); + + spu_transaction_init(card); + + /* write SPU register index */ + err = spi_write(card->spi, (u8 *)®_out, sizeof(u16)); + if (err) + goto out; + + err = spi_write(card->spi, buf, len); + +out: + spu_transaction_finish(card); + return err; +} + +static inline int spu_write_u16(struct if_spi_card *card, u16 reg, u16 val) +{ + return spu_write(card, reg, (u8 *)&val, sizeof(u16)); +} + +static inline int spu_write_u32(struct if_spi_card *card, u16 reg, u32 val) +{ + /* The lower 16 bits are written first. */ + u16 out[2]; + out[0] = val & 0xffff; + out[1] = (val & 0xffff0000) >> 16; + return spu_write(card, reg, (u8 *)&out, sizeof(u32)); +} + +static inline int spu_reg_is_port_reg(u16 reg) +{ + switch (reg) { + case IF_SPI_IO_RDWRPORT_REG: + case IF_SPI_CMD_RDWRPORT_REG: + case IF_SPI_DATA_RDWRPORT_REG: + return 1; + default: + return 0; + } +} + +static int spu_read(struct if_spi_card *card, u16 reg, u8 *buf, int len) +{ + unsigned int i, delay; + int err = 0; + u16 zero = 0; + u16 reg_out = reg | IF_SPI_READ_OPERATION_MASK; + + /* You must take an even number of bytes from the SPU, even if you + * don't care about the last one. */ + BUG_ON(len & 0x1); + + spu_transaction_init(card); + + /* write SPU register index */ + err = spi_write(card->spi, (u8 *)®_out, sizeof(u16)); + if (err) + goto out; + + delay = spu_reg_is_port_reg(reg) ? card->spu_port_delay : + card->spu_reg_delay; + if (card->use_dummy_writes) { + /* Clock in dummy cycles while the SPU fills the FIFO */ + for (i = 0; i < delay / 16; ++i) { + err = spi_write(card->spi, (u8 *)&zero, sizeof(u16)); + if (err) + return err; + } + } else { + /* Busy-wait while the SPU fills the FIFO */ + ndelay(100 + (delay * 10)); + } + + /* read in data */ + err = spi_read(card->spi, buf, len); + +out: + spu_transaction_finish(card); + return err; +} + +/* Read 16 bits from an SPI register */ +static inline int spu_read_u16(struct if_spi_card *card, u16 reg, u16 *val) +{ + return spu_read(card, reg, (u8 *)val, sizeof(u16)); +} + +/* Read 32 bits from an SPI register. + * The low 16 bits are read first. */ +static int spu_read_u32(struct if_spi_card *card, u16 reg, u32 *val) +{ + u16 buf[2]; + int err; + err = spu_read(card, reg, (u8 *)buf, sizeof(u32)); + if (!err) + *val = buf[0] | (buf[1] << 16); + return err; +} + +/* Keep reading 16 bits from an SPI register until you get the correct result. + * + * If mask = 0, the correct result is any non-zero number. + * If mask != 0, the correct result is any number where + * number & target_mask == target + * + * Returns -ETIMEDOUT if a second passes without the correct result. */ +static int spu_wait_for_u16(struct if_spi_card *card, u16 reg, + u16 target_mask, u16 target) +{ + int err; + unsigned long timeout = jiffies + 5*HZ; + while (1) { + u16 val; + err = spu_read_u16(card, reg, &val); + if (err) + return err; + if (target_mask) { + if ((val & target_mask) == target) + return 0; + } else { + if (val) + return 0; + } + udelay(100); + if (time_after(jiffies, timeout)) { + lbs_pr_err("%s: timeout with val=%02x, " + "target_mask=%02x, target=%02x\n", + __func__, val, target_mask, target); + return -ETIMEDOUT; + } + } +} + +/* Read 16 bits from an SPI register until you receive a specific value. + * Returns -ETIMEDOUT if a 4 tries pass without success. */ +static int spu_wait_for_u32(struct if_spi_card *card, u32 reg, u32 target) +{ + int err, try; + for (try = 0; try < 4; ++try) { + u32 val = 0; + err = spu_read_u32(card, reg, &val); + if (err) + return err; + if (val == target) + return 0; + mdelay(100); + } + return -ETIMEDOUT; +} + +static int spu_set_interrupt_mode(struct if_spi_card *card, + int suppress_host_int, + int auto_int) +{ + int err = 0; + + /* We can suppress a host interrupt by clearing the appropriate + * bit in the "host interrupt status mask" register */ + if (suppress_host_int) { + err = spu_write_u16(card, IF_SPI_HOST_INT_STATUS_MASK_REG, 0); + if (err) + return err; + } else { + err = spu_write_u16(card, IF_SPI_HOST_INT_STATUS_MASK_REG, + IF_SPI_HISM_TX_DOWNLOAD_RDY | + IF_SPI_HISM_RX_UPLOAD_RDY | + IF_SPI_HISM_CMD_DOWNLOAD_RDY | + IF_SPI_HISM_CARDEVENT | + IF_SPI_HISM_CMD_UPLOAD_RDY); + if (err) + return err; + } + + /* If auto-interrupts are on, the completion of certain transactions + * will trigger an interrupt automatically. If auto-interrupts + * are off, we need to set the "Card Interrupt Cause" register to + * trigger a card interrupt. */ + if (auto_int) { + err = spu_write_u16(card, IF_SPI_HOST_INT_CTRL_REG, + IF_SPI_HICT_TX_DOWNLOAD_OVER_AUTO | + IF_SPI_HICT_RX_UPLOAD_OVER_AUTO | + IF_SPI_HICT_CMD_DOWNLOAD_OVER_AUTO | + IF_SPI_HICT_CMD_UPLOAD_OVER_AUTO); + if (err) + return err; + } else { + err = spu_write_u16(card, IF_SPI_HOST_INT_STATUS_MASK_REG, 0); + if (err) + return err; + } + return err; +} + +static int spu_get_chip_revision(struct if_spi_card *card, + u16 *card_id, u8 *card_rev) +{ + int err = 0; + u32 dev_ctrl; + err = spu_read_u32(card, IF_SPI_DEVICEID_CTRL_REG, &dev_ctrl); + if (err) + return err; + *card_id = IF_SPI_DEVICEID_CTRL_REG_TO_CARD_ID(dev_ctrl); + *card_rev = IF_SPI_DEVICEID_CTRL_REG_TO_CARD_REV(dev_ctrl); + return err; +} + +static int spu_set_bus_mode(struct if_spi_card *card, u16 mode) +{ + int err = 0; + u16 rval; + /* set bus mode */ + err = spu_write_u16(card, IF_SPI_SPU_BUS_MODE_REG, mode); + if (err) + return err; + /* Check that we were able to read back what we just wrote. */ + err = spu_read_u16(card, IF_SPI_SPU_BUS_MODE_REG, &rval); + if (err) + return err; + if (rval != mode) { + lbs_pr_err("Can't read bus mode register.\n"); + return -EIO; + } + return 0; +} + +static int spu_init(struct if_spi_card *card, int use_dummy_writes) +{ + int err = 0; + u32 delay; + + /* We have to start up in timed delay mode so that we can safely + * read the Delay Read Register. */ + card->use_dummy_writes = 0; + err = spu_set_bus_mode(card, + IF_SPI_BUS_MODE_SPI_CLOCK_PHASE_RISING | + IF_SPI_BUS_MODE_DELAY_METHOD_TIMED | + IF_SPI_BUS_MODE_16_BIT_ADDRESS_16_BIT_DATA); + if (err) + return err; + card->spu_port_delay = 1000; + card->spu_reg_delay = 1000; + err = spu_read_u32(card, IF_SPI_DELAY_READ_REG, &delay); + if (err) + return err; + card->spu_port_delay = delay & 0x0000ffff; + card->spu_reg_delay = (delay & 0xffff0000) >> 16; + + /* If dummy clock delay mode has been requested, switch to it now */ + if (use_dummy_writes) { + card->use_dummy_writes = 1; + err = spu_set_bus_mode(card, + IF_SPI_BUS_MODE_SPI_CLOCK_PHASE_RISING | + IF_SPI_BUS_MODE_DELAY_METHOD_DUMMY_CLOCK | + IF_SPI_BUS_MODE_16_BIT_ADDRESS_16_BIT_DATA); + if (err) + return err; + } + + lbs_deb_spi("Initialized SPU unit. " + "spu_port_delay=0x%04lx, spu_reg_delay=0x%04lx\n", + card->spu_port_delay, card->spu_reg_delay); + return err; +} + +/* + * Firmware Loading + */ + +static int if_spi_prog_helper_firmware(struct if_spi_card *card) +{ + int err = 0; + const struct firmware *firmware = NULL; + int bytes_remaining; + const u8 *fw; + u8 temp[HELPER_FW_LOAD_CHUNK_SZ]; + struct spi_device *spi = card->spi; + + lbs_deb_enter(LBS_DEB_SPI); + + err = spu_set_interrupt_mode(card, 1, 0); + if (err) + goto out; + /* Get helper firmware image */ + err = request_firmware(&firmware, card->helper_fw_name, &spi->dev); + if (err) { + lbs_pr_err("request_firmware failed with err = %d\n", err); + goto out; + } + bytes_remaining = firmware->size; + fw = firmware->data; + + /* Load helper firmware image */ + while (bytes_remaining > 0) { + /* Scratch pad 1 should contain the number of bytes we + * want to download to the firmware */ + err = spu_write_u16(card, IF_SPI_SCRATCH_1_REG, + HELPER_FW_LOAD_CHUNK_SZ); + if (err) + goto release_firmware; + + err = spu_wait_for_u16(card, IF_SPI_HOST_INT_STATUS_REG, + IF_SPI_HIST_CMD_DOWNLOAD_RDY, + IF_SPI_HIST_CMD_DOWNLOAD_RDY); + if (err) + goto release_firmware; + + /* Feed the data into the command read/write port reg + * in chunks of 64 bytes */ + memset(temp, 0, sizeof(temp)); + memcpy(temp, fw, + min(bytes_remaining, HELPER_FW_LOAD_CHUNK_SZ)); + mdelay(10); + err = spu_write(card, IF_SPI_CMD_RDWRPORT_REG, + temp, HELPER_FW_LOAD_CHUNK_SZ); + if (err) + goto release_firmware; + + /* Interrupt the boot code */ + err = spu_write_u16(card, IF_SPI_HOST_INT_STATUS_REG, 0); + if (err) + goto release_firmware; + err = spu_write_u16(card, IF_SPI_CARD_INT_CAUSE_REG, + IF_SPI_CIC_CMD_DOWNLOAD_OVER); + if (err) + goto release_firmware; + bytes_remaining -= HELPER_FW_LOAD_CHUNK_SZ; + fw += HELPER_FW_LOAD_CHUNK_SZ; + } + + /* Once the helper / single stage firmware download is complete, + * write 0 to scratch pad 1 and interrupt the + * bootloader. This completes the helper download. */ + err = spu_write_u16(card, IF_SPI_SCRATCH_1_REG, FIRMWARE_DNLD_OK); + if (err) + goto release_firmware; + err = spu_write_u16(card, IF_SPI_HOST_INT_STATUS_REG, 0); + if (err) + goto release_firmware; + err = spu_write_u16(card, IF_SPI_CARD_INT_CAUSE_REG, + IF_SPI_CIC_CMD_DOWNLOAD_OVER); + goto release_firmware; + + lbs_deb_spi("waiting for helper to boot...\n"); + +release_firmware: + release_firmware(firmware); +out: + if (err) + lbs_pr_err("failed to load helper firmware (err=%d)\n", err); + lbs_deb_leave_args(LBS_DEB_SPI, "err %d", err); + return err; +} + +/* Returns the length of the next packet the firmware expects us to send + * Sets crc_err if the previous transfer had a CRC error. */ +static int if_spi_prog_main_firmware_check_len(struct if_spi_card *card, + int *crc_err) +{ + u16 len; + int err = 0; + + /* wait until the host interrupt status register indicates + * that we are ready to download */ + err = spu_wait_for_u16(card, IF_SPI_HOST_INT_STATUS_REG, + IF_SPI_HIST_CMD_DOWNLOAD_RDY, + IF_SPI_HIST_CMD_DOWNLOAD_RDY); + if (err) { + lbs_pr_err("timed out waiting for host_int_status\n"); + return err; + } + + /* Ask the device how many bytes of firmware it wants. */ + err = spu_read_u16(card, IF_SPI_SCRATCH_1_REG, &len); + if (err) + return err; + + if (len > IF_SPI_CMD_BUF_SIZE) { + lbs_pr_err("firmware load device requested a larger " + "tranfer than we are prepared to " + "handle. (len = %d)\n", len); + return -EIO; + } + if (len & 0x1) { + lbs_deb_spi("%s: crc error\n", __func__); + len &= ~0x1; + *crc_err = 1; + } else + *crc_err = 0; + + return len; +} + +static int if_spi_prog_main_firmware(struct if_spi_card *card) +{ + int len, prev_len; + int bytes, crc_err = 0, err = 0; + const struct firmware *firmware = NULL; + const u8 *fw; + struct spi_device *spi = card->spi; + u16 num_crc_errs; + + lbs_deb_enter(LBS_DEB_SPI); + + err = spu_set_interrupt_mode(card, 1, 0); + if (err) + goto out; + + /* Get firmware image */ + err = request_firmware(&firmware, card->main_fw_name, &spi->dev); + if (err) { + lbs_pr_err("%s: can't get firmware '%s' from kernel. " + "err = %d\n", __func__, card->main_fw_name, err); + goto out; + } + + err = spu_wait_for_u16(card, IF_SPI_SCRATCH_1_REG, 0, 0); + if (err) { + lbs_pr_err("%s: timed out waiting for initial " + "scratch reg = 0\n", __func__); + goto release_firmware; + } + + num_crc_errs = 0; + prev_len = 0; + bytes = firmware->size; + fw = firmware->data; + while ((len = if_spi_prog_main_firmware_check_len(card, &crc_err))) { + if (len < 0) { + err = len; + goto release_firmware; + } + if (bytes < 0) { + /* If there are no more bytes left, we would normally + * expect to have terminated with len = 0 */ + lbs_pr_err("Firmware load wants more bytes " + "than we have to offer.\n"); + break; + } + if (crc_err) { + /* Previous transfer failed. */ + if (++num_crc_errs > MAX_MAIN_FW_LOAD_CRC_ERR) { + lbs_pr_err("Too many CRC errors encountered " + "in firmware load.\n"); + err = -EIO; + goto release_firmware; + } + } else { + /* Previous transfer succeeded. Advance counters. */ + bytes -= prev_len; + fw += prev_len; + } + if (bytes < len) { + memset(card->cmd_buffer, 0, len); + memcpy(card->cmd_buffer, fw, bytes); + } else + memcpy(card->cmd_buffer, fw, len); + + err = spu_write_u16(card, IF_SPI_HOST_INT_STATUS_REG, 0); + if (err) + goto release_firmware; + err = spu_write(card, IF_SPI_CMD_RDWRPORT_REG, + card->cmd_buffer, len); + if (err) + goto release_firmware; + err = spu_write_u16(card, IF_SPI_CARD_INT_CAUSE_REG , + IF_SPI_CIC_CMD_DOWNLOAD_OVER); + if (err) + goto release_firmware; + prev_len = len; + } + if (bytes > prev_len) { + lbs_pr_err("firmware load wants fewer bytes than " + "we have to offer.\n"); + } + + /* Confirm firmware download */ + err = spu_wait_for_u32(card, IF_SPI_SCRATCH_4_REG, + SUCCESSFUL_FW_DOWNLOAD_MAGIC); + if (err) { + lbs_pr_err("failed to confirm the firmware download\n"); + goto release_firmware; + } + +release_firmware: + release_firmware(firmware); + +out: + if (err) + lbs_pr_err("failed to load firmware (err=%d)\n", err); + lbs_deb_leave_args(LBS_DEB_SPI, "err %d", err); + return err; +} + +/* + * SPI Transfer Thread + * + * The SPI thread handles all SPI transfers, so there is no need for a lock. + */ + +/* Move a command from the card to the host */ +static int if_spi_c2h_cmd(struct if_spi_card *card) +{ + struct lbs_private *priv = card->priv; + unsigned long flags; + int err = 0; + u16 len; + u8 i; + + /* We need a buffer big enough to handle whatever people send to + * hw_host_to_card */ + BUILD_BUG_ON(IF_SPI_CMD_BUF_SIZE < LBS_CMD_BUFFER_SIZE); + BUILD_BUG_ON(IF_SPI_CMD_BUF_SIZE < LBS_UPLD_SIZE); + + /* It's just annoying if the buffer size isn't a multiple of 4, because + * then we might have len < IF_SPI_CMD_BUF_SIZE but + * ALIGN(len, 4) > IF_SPI_CMD_BUF_SIZE */ + BUILD_BUG_ON(IF_SPI_CMD_BUF_SIZE % 4 != 0); + + lbs_deb_enter(LBS_DEB_SPI); + + /* How many bytes are there to read? */ + err = spu_read_u16(card, IF_SPI_SCRATCH_2_REG, &len); + if (err) + goto out; + if (!len) { + lbs_pr_err("%s: error: card has no data for host\n", + __func__); + err = -EINVAL; + goto out; + } else if (len > IF_SPI_CMD_BUF_SIZE) { + lbs_pr_err("%s: error: response packet too large: " + "%d bytes, but maximum is %d\n", + __func__, len, IF_SPI_CMD_BUF_SIZE); + err = -EINVAL; + goto out; + } + + /* Read the data from the WLAN module into our command buffer */ + err = spu_read(card, IF_SPI_CMD_RDWRPORT_REG, + card->cmd_buffer, ALIGN(len, 4)); + if (err) + goto out; + + spin_lock_irqsave(&priv->driver_lock, flags); + i = (priv->resp_idx == 0) ? 1 : 0; + BUG_ON(priv->resp_len[i]); + priv->resp_len[i] = len; + memcpy(priv->resp_buf[i], card->cmd_buffer, len); + lbs_notify_command_response(priv, i); + spin_unlock_irqrestore(&priv->driver_lock, flags); + +out: + if (err) + lbs_pr_err("%s: err=%d\n", __func__, err); + lbs_deb_leave(LBS_DEB_SPI); + return err; +} + +/* Move data from the card to the host */ +static int if_spi_c2h_data(struct if_spi_card *card) +{ + struct sk_buff *skb; + char *data; + u16 len; + int err = 0; + + lbs_deb_enter(LBS_DEB_SPI); + + /* How many bytes are there to read? */ + err = spu_read_u16(card, IF_SPI_SCRATCH_1_REG, &len); + if (err) + goto out; + if (!len) { + lbs_pr_err("%s: error: card has no data for host\n", + __func__); + err = -EINVAL; + goto out; + } else if (len > MRVDRV_ETH_RX_PACKET_BUFFER_SIZE) { + lbs_pr_err("%s: error: card has %d bytes of data, but " + "our maximum skb size is %u\n", + __func__, len, MRVDRV_ETH_RX_PACKET_BUFFER_SIZE); + err = -EINVAL; + goto out; + } + + /* TODO: should we allocate a smaller skb if we have less data? */ + skb = dev_alloc_skb(MRVDRV_ETH_RX_PACKET_BUFFER_SIZE); + if (!skb) { + err = -ENOBUFS; + goto out; + } + skb_reserve(skb, IPFIELD_ALIGN_OFFSET); + data = skb_put(skb, len); + + /* Read the data from the WLAN module into our skb... */ + err = spu_read(card, IF_SPI_DATA_RDWRPORT_REG, data, ALIGN(len, 4)); + if (err) + goto free_skb; + + /* pass the SKB to libertas */ + err = lbs_process_rxed_packet(card->priv, skb); + if (err) + goto free_skb; + + /* success */ + goto out; + +free_skb: + dev_kfree_skb(skb); +out: + if (err) + lbs_pr_err("%s: err=%d\n", __func__, err); + lbs_deb_leave(LBS_DEB_SPI); + return err; +} + +/* Move data or a command from the host to the card. */ +static void if_spi_h2c(struct if_spi_card *card, + struct if_spi_packet *packet, int type) +{ + int err = 0; + u16 int_type, port_reg; + + switch (type) { + case MVMS_DAT: + int_type = IF_SPI_CIC_TX_DOWNLOAD_OVER; + port_reg = IF_SPI_DATA_RDWRPORT_REG; + break; + case MVMS_CMD: + int_type = IF_SPI_CIC_CMD_DOWNLOAD_OVER; + port_reg = IF_SPI_CMD_RDWRPORT_REG; + break; + default: + lbs_pr_err("can't transfer buffer of type %d\n", type); + err = -EINVAL; + goto out; + } + + /* Write the data to the card */ + err = spu_write(card, port_reg, packet->buffer, packet->blen); + if (err) + goto out; + +out: + kfree(packet); + + if (err) + lbs_pr_err("%s: error %d\n", __func__, err); +} + +/* Inform the host about a card event */ +static void if_spi_e2h(struct if_spi_card *card) +{ + int err = 0; + unsigned long flags; + u32 cause; + struct lbs_private *priv = card->priv; + + err = spu_read_u32(card, IF_SPI_SCRATCH_3_REG, &cause); + if (err) + goto out; + + spin_lock_irqsave(&priv->driver_lock, flags); + lbs_queue_event(priv, cause & 0xff); + spin_unlock_irqrestore(&priv->driver_lock, flags); + +out: + if (err) + lbs_pr_err("%s: error %d\n", __func__, err); +} + +static int lbs_spi_thread(void *data) +{ + int err; + struct if_spi_card *card = data; + u16 hiStatus; + unsigned long flags; + struct if_spi_packet *packet; + + while (1) { + /* Wait to be woken up by one of two things. First, our ISR + * could tell us that something happened on the WLAN. + * Secondly, libertas could call hw_host_to_card with more + * data, which we might be able to send. + */ + do { + err = down_interruptible(&card->spi_ready); + if (!card->run_thread) { + up(&card->spi_thread_terminated); + do_exit(0); + } + } while (err == EINTR); + + /* Read the host interrupt status register to see what we + * can do. */ + err = spu_read_u16(card, IF_SPI_HOST_INT_STATUS_REG, + &hiStatus); + if (err) { + lbs_pr_err("I/O error\n"); + goto err; + } + + if (hiStatus & IF_SPI_HIST_CMD_UPLOAD_RDY) + err = if_spi_c2h_cmd(card); + if (err) + goto err; + if (hiStatus & IF_SPI_HIST_RX_UPLOAD_RDY) + err = if_spi_c2h_data(card); + if (err) + goto err; + if (hiStatus & IF_SPI_HIST_CMD_DOWNLOAD_RDY) { + /* This means two things. First of all, + * if there was a previous command sent, the card has + * successfully received it. + * Secondly, it is now ready to download another + * command. + */ + lbs_host_to_card_done(card->priv); + + /* Do we have any command packets from the host to + * send? */ + packet = NULL; + spin_lock_irqsave(&card->buffer_lock, flags); + if (!list_empty(&card->cmd_packet_list)) { + packet = (struct if_spi_packet *)(card-> + cmd_packet_list.next); + list_del(&packet->list); + } + spin_unlock_irqrestore(&card->buffer_lock, flags); + + if (packet) + if_spi_h2c(card, packet, MVMS_CMD); + } + if (hiStatus & IF_SPI_HIST_TX_DOWNLOAD_RDY) { + /* Do we have any data packets from the host to + * send? */ + packet = NULL; + spin_lock_irqsave(&card->buffer_lock, flags); + if (!list_empty(&card->data_packet_list)) { + packet = (struct if_spi_packet *)(card-> + data_packet_list.next); + list_del(&packet->list); + } + spin_unlock_irqrestore(&card->buffer_lock, flags); + + if (packet) + if_spi_h2c(card, packet, MVMS_DAT); + } + if (hiStatus & IF_SPI_HIST_CARD_EVENT) + if_spi_e2h(card); + +err: + if (err) + lbs_pr_err("%s: got error %d\n", __func__, err); + } +} + +/* Block until lbs_spi_thread thread has terminated */ +static void if_spi_terminate_spi_thread(struct if_spi_card *card) +{ + /* It would be nice to use kthread_stop here, but that function + * can't wake threads waiting for a semaphore. */ + card->run_thread = 0; + up(&card->spi_ready); + down(&card->spi_thread_terminated); +} + +/* + * Host to Card + * + * Called from Libertas to transfer some data to the WLAN device + * We can't sleep here. */ +static int if_spi_host_to_card(struct lbs_private *priv, + u8 type, u8 *buf, u16 nb) +{ + int err = 0; + unsigned long flags; + struct if_spi_card *card = priv->card; + struct if_spi_packet *packet; + u16 blen; + + lbs_deb_enter_args(LBS_DEB_SPI, "type %d, bytes %d", type, nb); + + if (nb == 0) { + lbs_pr_err("%s: invalid size requested: %d\n", __func__, nb); + err = -EINVAL; + goto out; + } + blen = ALIGN(nb, 4); + packet = kzalloc(sizeof(struct if_spi_packet) + blen, GFP_ATOMIC); + if (!packet) { + err = -ENOMEM; + goto out; + } + packet->blen = blen; + memcpy(packet->buffer, buf, nb); + memset(packet->buffer + nb, 0, blen - nb); + + switch (type) { + case MVMS_CMD: + priv->dnld_sent = DNLD_CMD_SENT; + spin_lock_irqsave(&card->buffer_lock, flags); + list_add_tail(&packet->list, &card->cmd_packet_list); + spin_unlock_irqrestore(&card->buffer_lock, flags); + break; + case MVMS_DAT: + priv->dnld_sent = DNLD_DATA_SENT; + spin_lock_irqsave(&card->buffer_lock, flags); + list_add_tail(&packet->list, &card->data_packet_list); + spin_unlock_irqrestore(&card->buffer_lock, flags); + break; + default: + lbs_pr_err("can't transfer buffer of type %d", type); + err = -EINVAL; + break; + } + + /* Wake up the spi thread */ + up(&card->spi_ready); +out: + lbs_deb_leave_args(LBS_DEB_SPI, "err=%d", err); + return err; +} + +/* + * Host Interrupts + * + * Service incoming interrupts from the WLAN device. We can't sleep here, so + * don't try to talk on the SPI bus, just wake up the SPI thread. + */ +static irqreturn_t if_spi_host_interrupt(int irq, void *dev_id) +{ + struct if_spi_card *card = dev_id; + + up(&card->spi_ready); + return IRQ_HANDLED; +} + +/* + * SPI callbacks + */ + +static int if_spi_calculate_fw_names(u16 card_id, + char *helper_fw, char *main_fw) +{ + int i; + for (i = 0; i < ARRAY_SIZE(chip_id_to_device_name); ++i) { + if (card_id == chip_id_to_device_name[i].chip_id) + break; + } + if (i == ARRAY_SIZE(chip_id_to_device_name)) { + lbs_pr_err("Unsupported chip_id: 0x%02x\n", card_id); + return -EAFNOSUPPORT; + } + snprintf(helper_fw, FIRMWARE_NAME_MAX, "libertas/gspi%d_hlp.bin", + chip_id_to_device_name[i].name); + snprintf(main_fw, FIRMWARE_NAME_MAX, "libertas/gspi%d.bin", + chip_id_to_device_name[i].name); + return 0; +} + +static int __devinit if_spi_probe(struct spi_device *spi) +{ + struct if_spi_card *card; + struct lbs_private *priv = NULL; + struct libertas_spi_platform_data *pdata = spi->dev.platform_data; + int err = 0; + u32 scratch; + + lbs_deb_enter(LBS_DEB_SPI); + + /* Allocate card structure to represent this specific device */ + card = kzalloc(sizeof(struct if_spi_card), GFP_KERNEL); + if (!card) { + err = -ENOMEM; + goto out; + } + spi_set_drvdata(spi, card); + card->spi = spi; + card->gpio_cs = pdata->gpio_cs; + card->prev_xfer_time = jiffies; + + sema_init(&card->spi_ready, 0); + sema_init(&card->spi_thread_terminated, 0); + INIT_LIST_HEAD(&card->cmd_packet_list); + INIT_LIST_HEAD(&card->data_packet_list); + spin_lock_init(&card->buffer_lock); + + /* set up GPIO CS line. TODO: use regular CS line */ + err = gpio_request(card->gpio_cs, "if_spi_gpio_chip_select"); + if (err) + goto free_card; + err = gpio_direction_output(card->gpio_cs, 1); + if (err) + goto free_gpio; + + /* Initialize the SPI Interface Unit */ + err = spu_init(card, pdata->use_dummy_writes); + if (err) + goto free_gpio; + err = spu_get_chip_revision(card, &card->card_id, &card->card_rev); + if (err) + goto free_gpio; + + /* Firmware load */ + err = spu_read_u32(card, IF_SPI_SCRATCH_4_REG, &scratch); + if (err) + goto free_gpio; + if (scratch == SUCCESSFUL_FW_DOWNLOAD_MAGIC) + lbs_deb_spi("Firmware is already loaded for " + "Marvell WLAN 802.11 adapter\n"); + else { + err = if_spi_calculate_fw_names(card->card_id, + card->helper_fw_name, card->main_fw_name); + if (err) + goto free_gpio; + + lbs_deb_spi("Initializing FW for Marvell WLAN 802.11 adapter " + "(chip_id = 0x%04x, chip_rev = 0x%02x) " + "attached to SPI bus_num %d, chip_select %d. " + "spi->max_speed_hz=%d\n", + card->card_id, card->card_rev, + spi->master->bus_num, spi->chip_select, + spi->max_speed_hz); + err = if_spi_prog_helper_firmware(card); + if (err) + goto free_gpio; + err = if_spi_prog_main_firmware(card); + if (err) + goto free_gpio; + lbs_deb_spi("loaded FW for Marvell WLAN 802.11 adapter\n"); + } + + err = spu_set_interrupt_mode(card, 0, 1); + if (err) + goto free_gpio; + + /* Register our card with libertas. + * This will call alloc_etherdev */ + priv = lbs_add_card(card, &spi->dev); + if (!priv) { + err = -ENOMEM; + goto free_gpio; + } + card->priv = priv; + priv->card = card; + priv->hw_host_to_card = if_spi_host_to_card; + priv->fw_ready = 1; + priv->ps_supported = 1; + + /* Initialize interrupt handling stuff. */ + card->run_thread = 1; + card->spi_thread = kthread_run(lbs_spi_thread, card, "lbs_spi_thread"); + if (IS_ERR(card->spi_thread)) { + card->run_thread = 0; + err = PTR_ERR(card->spi_thread); + lbs_pr_err("error creating SPI thread: err=%d\n", err); + goto remove_card; + } + err = request_irq(spi->irq, if_spi_host_interrupt, + IRQF_TRIGGER_FALLING, "libertas_spi", card); + if (err) { + lbs_pr_err("can't get host irq line-- request_irq failed\n"); + goto terminate_thread; + } + + /* Start the card. + * This will call register_netdev, and we'll start + * getting interrupts... */ + err = lbs_start_card(priv); + if (err) + goto release_irq; + + lbs_deb_spi("Finished initializing WLAN module.\n"); + + /* successful exit */ + goto out; + +release_irq: + free_irq(spi->irq, card); +terminate_thread: + if_spi_terminate_spi_thread(card); +remove_card: + lbs_remove_card(priv); /* will call free_netdev */ +free_gpio: + gpio_free(card->gpio_cs); +free_card: + free_if_spi_card(card); +out: + lbs_deb_leave_args(LBS_DEB_SPI, "err %d\n", err); + return err; +} + +static int __devexit libertas_spi_remove(struct spi_device *spi) +{ + struct if_spi_card *card = spi_get_drvdata(spi); + struct lbs_private *priv = card->priv; + + lbs_deb_spi("libertas_spi_remove\n"); + lbs_deb_enter(LBS_DEB_SPI); + priv->surpriseremoved = 1; + + lbs_stop_card(priv); + free_irq(spi->irq, card); + if_spi_terminate_spi_thread(card); + lbs_remove_card(priv); /* will call free_netdev */ + gpio_free(card->gpio_cs); + free_if_spi_card(card); + lbs_deb_leave(LBS_DEB_SPI); + return 0; +} + +static struct spi_driver libertas_spi_driver = { + .probe = if_spi_probe, + .remove = __devexit_p(libertas_spi_remove), + .driver = { + .name = "libertas_spi", + .bus = &spi_bus_type, + .owner = THIS_MODULE, + }, +}; + +/* + * Module functions + */ + +static int __init if_spi_init_module(void) +{ + int ret = 0; + lbs_deb_enter(LBS_DEB_SPI); + printk(KERN_INFO "libertas_spi: Libertas SPI driver\n"); + ret = spi_register_driver(&libertas_spi_driver); + lbs_deb_leave(LBS_DEB_SPI); + return ret; +} + +static void __exit if_spi_exit_module(void) +{ + lbs_deb_enter(LBS_DEB_SPI); + spi_unregister_driver(&libertas_spi_driver); + lbs_deb_leave(LBS_DEB_SPI); +} + +module_init(if_spi_init_module); +module_exit(if_spi_exit_module); + +MODULE_DESCRIPTION("Libertas SPI WLAN Driver"); +MODULE_AUTHOR("Andrey Yurovsky <andrey@cozybit.com>, " + "Colin McCabe <colin@cozybit.com>"); +MODULE_LICENSE("GPL"); |