+++ /dev/null
-/*
- * ChromeOS EC multi-function device (SPI)
- *
- * Copyright (C) 2012 Google, Inc
- *
- * This software is licensed under the terms of the GNU General Public
- * License version 2, as published by the Free Software Foundation, and
- * may be copied, distributed, and modified under those terms.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- */
-
-#include <linux/delay.h>
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/mfd/cros_ec.h>
-#include <linux/mfd/cros_ec_commands.h>
-#include <linux/of.h>
-#include <linux/platform_device.h>
-#include <linux/slab.h>
-#include <linux/spi/spi.h>
-
-
-/* The header byte, which follows the preamble */
-#define EC_MSG_HEADER 0xec
-
-/*
- * Number of EC preamble bytes we read at a time. Since it takes
- * about 400-500us for the EC to respond there is not a lot of
- * point in tuning this. If the EC could respond faster then
- * we could increase this so that might expect the preamble and
- * message to occur in a single transaction. However, the maximum
- * SPI transfer size is 256 bytes, so at 5MHz we need a response
- * time of perhaps <320us (200 bytes / 1600 bits).
- */
-#define EC_MSG_PREAMBLE_COUNT 32
-
-/*
- * Allow for a long time for the EC to respond. We support i2c
- * tunneling and support fairly long messages for the tunnel (249
- * bytes long at the moment). If we're talking to a 100 kHz device
- * on the other end and need to transfer ~256 bytes, then we need:
- * 10 us/bit * ~10 bits/byte * ~256 bytes = ~25ms
- *
- * We'll wait 8 times that to handle clock stretching and other
- * paranoia. Note that some battery gas gauge ICs claim to have a
- * clock stretch of 144ms in rare situations. That's incentive for
- * not directly passing i2c through, but it's too late for that for
- * existing hardware.
- *
- * It's pretty unlikely that we'll really see a 249 byte tunnel in
- * anything other than testing. If this was more common we might
- * consider having slow commands like this require a GET_STATUS
- * wait loop. The 'flash write' command would be another candidate
- * for this, clocking in at 2-3ms.
- */
-#define EC_MSG_DEADLINE_MS 200
-
-/*
- * Time between raising the SPI chip select (for the end of a
- * transaction) and dropping it again (for the next transaction).
- * If we go too fast, the EC will miss the transaction. We know that we
- * need at least 70 us with the 16 MHz STM32 EC, so go with 200 us to be
- * safe.
- */
-#define EC_SPI_RECOVERY_TIME_NS (200 * 1000)
-
-/**
- * struct cros_ec_spi - information about a SPI-connected EC
- *
- * @spi: SPI device we are connected to
- * @last_transfer_ns: time that we last finished a transfer.
- * @start_of_msg_delay: used to set the delay_usecs on the spi_transfer that
- * is sent when we want to turn on CS at the start of a transaction.
- * @end_of_msg_delay: used to set the delay_usecs on the spi_transfer that
- * is sent when we want to turn off CS at the end of a transaction.
- */
-struct cros_ec_spi {
- struct spi_device *spi;
- s64 last_transfer_ns;
- unsigned int start_of_msg_delay;
- unsigned int end_of_msg_delay;
-};
-
-static void debug_packet(struct device *dev, const char *name, u8 *ptr,
- int len)
-{
-#ifdef DEBUG
- int i;
-
- dev_dbg(dev, "%s: ", name);
- for (i = 0; i < len; i++)
- pr_cont(" %02x", ptr[i]);
-
- pr_cont("\n");
-#endif
-}
-
-static int terminate_request(struct cros_ec_device *ec_dev)
-{
- struct cros_ec_spi *ec_spi = ec_dev->priv;
- struct spi_message msg;
- struct spi_transfer trans;
- int ret;
-
- /*
- * Turn off CS, possibly adding a delay to ensure the rising edge
- * doesn't come too soon after the end of the data.
- */
- spi_message_init(&msg);
- memset(&trans, 0, sizeof(trans));
- trans.delay_usecs = ec_spi->end_of_msg_delay;
- spi_message_add_tail(&trans, &msg);
-
- ret = spi_sync_locked(ec_spi->spi, &msg);
-
- /* Reset end-of-response timer */
- ec_spi->last_transfer_ns = ktime_get_ns();
- if (ret < 0) {
- dev_err(ec_dev->dev,
- "cs-deassert spi transfer failed: %d\n",
- ret);
- }
-
- return ret;
-}
-
-/**
- * receive_n_bytes - receive n bytes from the EC.
- *
- * Assumes buf is a pointer into the ec_dev->din buffer
- */
-static int receive_n_bytes(struct cros_ec_device *ec_dev, u8 *buf, int n)
-{
- struct cros_ec_spi *ec_spi = ec_dev->priv;
- struct spi_transfer trans;
- struct spi_message msg;
- int ret;
-
- BUG_ON(buf - ec_dev->din + n > ec_dev->din_size);
-
- memset(&trans, 0, sizeof(trans));
- trans.cs_change = 1;
- trans.rx_buf = buf;
- trans.len = n;
-
- spi_message_init(&msg);
- spi_message_add_tail(&trans, &msg);
- ret = spi_sync_locked(ec_spi->spi, &msg);
- if (ret < 0)
- dev_err(ec_dev->dev, "spi transfer failed: %d\n", ret);
-
- return ret;
-}
-
-/**
- * cros_ec_spi_receive_packet - Receive a packet from the EC.
- *
- * This function has two phases: reading the preamble bytes (since if we read
- * data from the EC before it is ready to send, we just get preamble) and
- * reading the actual message.
- *
- * The received data is placed into ec_dev->din.
- *
- * @ec_dev: ChromeOS EC device
- * @need_len: Number of message bytes we need to read
- */
-static int cros_ec_spi_receive_packet(struct cros_ec_device *ec_dev,
- int need_len)
-{
- struct ec_host_response *response;
- u8 *ptr, *end;
- int ret;
- unsigned long deadline;
- int todo;
-
- BUG_ON(ec_dev->din_size < EC_MSG_PREAMBLE_COUNT);
-
- /* Receive data until we see the header byte */
- deadline = jiffies + msecs_to_jiffies(EC_MSG_DEADLINE_MS);
- while (true) {
- unsigned long start_jiffies = jiffies;
-
- ret = receive_n_bytes(ec_dev,
- ec_dev->din,
- EC_MSG_PREAMBLE_COUNT);
- if (ret < 0)
- return ret;
-
- ptr = ec_dev->din;
- for (end = ptr + EC_MSG_PREAMBLE_COUNT; ptr != end; ptr++) {
- if (*ptr == EC_SPI_FRAME_START) {
- dev_dbg(ec_dev->dev, "msg found at %zd\n",
- ptr - ec_dev->din);
- break;
- }
- }
- if (ptr != end)
- break;
-
- /*
- * Use the time at the start of the loop as a timeout. This
- * gives us one last shot at getting the transfer and is useful
- * in case we got context switched out for a while.
- */
- if (time_after(start_jiffies, deadline)) {
- dev_warn(ec_dev->dev, "EC failed to respond in time\n");
- return -ETIMEDOUT;
- }
- }
-
- /*
- * ptr now points to the header byte. Copy any valid data to the
- * start of our buffer
- */
- todo = end - ++ptr;
- BUG_ON(todo < 0 || todo > ec_dev->din_size);
- todo = min(todo, need_len);
- memmove(ec_dev->din, ptr, todo);
- ptr = ec_dev->din + todo;
- dev_dbg(ec_dev->dev, "need %d, got %d bytes from preamble\n",
- need_len, todo);
- need_len -= todo;
-
- /* If the entire response struct wasn't read, get the rest of it. */
- if (todo < sizeof(*response)) {
- ret = receive_n_bytes(ec_dev, ptr, sizeof(*response) - todo);
- if (ret < 0)
- return -EBADMSG;
- ptr += (sizeof(*response) - todo);
- todo = sizeof(*response);
- }
-
- response = (struct ec_host_response *)ec_dev->din;
-
- /* Abort if data_len is too large. */
- if (response->data_len > ec_dev->din_size)
- return -EMSGSIZE;
-
- /* Receive data until we have it all */
- while (need_len > 0) {
- /*
- * We can't support transfers larger than the SPI FIFO size
- * unless we have DMA. We don't have DMA on the ISP SPI ports
- * for Exynos. We need a way of asking SPI driver for
- * maximum-supported transfer size.
- */
- todo = min(need_len, 256);
- dev_dbg(ec_dev->dev, "loop, todo=%d, need_len=%d, ptr=%zd\n",
- todo, need_len, ptr - ec_dev->din);
-
- ret = receive_n_bytes(ec_dev, ptr, todo);
- if (ret < 0)
- return ret;
-
- ptr += todo;
- need_len -= todo;
- }
-
- dev_dbg(ec_dev->dev, "loop done, ptr=%zd\n", ptr - ec_dev->din);
-
- return 0;
-}
-
-/**
- * cros_ec_spi_receive_response - Receive a response from the EC.
- *
- * This function has two phases: reading the preamble bytes (since if we read
- * data from the EC before it is ready to send, we just get preamble) and
- * reading the actual message.
- *
- * The received data is placed into ec_dev->din.
- *
- * @ec_dev: ChromeOS EC device
- * @need_len: Number of message bytes we need to read
- */
-static int cros_ec_spi_receive_response(struct cros_ec_device *ec_dev,
- int need_len)
-{
- u8 *ptr, *end;
- int ret;
- unsigned long deadline;
- int todo;
-
- BUG_ON(ec_dev->din_size < EC_MSG_PREAMBLE_COUNT);
-
- /* Receive data until we see the header byte */
- deadline = jiffies + msecs_to_jiffies(EC_MSG_DEADLINE_MS);
- while (true) {
- unsigned long start_jiffies = jiffies;
-
- ret = receive_n_bytes(ec_dev,
- ec_dev->din,
- EC_MSG_PREAMBLE_COUNT);
- if (ret < 0)
- return ret;
-
- ptr = ec_dev->din;
- for (end = ptr + EC_MSG_PREAMBLE_COUNT; ptr != end; ptr++) {
- if (*ptr == EC_SPI_FRAME_START) {
- dev_dbg(ec_dev->dev, "msg found at %zd\n",
- ptr - ec_dev->din);
- break;
- }
- }
- if (ptr != end)
- break;
-
- /*
- * Use the time at the start of the loop as a timeout. This
- * gives us one last shot at getting the transfer and is useful
- * in case we got context switched out for a while.
- */
- if (time_after(start_jiffies, deadline)) {
- dev_warn(ec_dev->dev, "EC failed to respond in time\n");
- return -ETIMEDOUT;
- }
- }
-
- /*
- * ptr now points to the header byte. Copy any valid data to the
- * start of our buffer
- */
- todo = end - ++ptr;
- BUG_ON(todo < 0 || todo > ec_dev->din_size);
- todo = min(todo, need_len);
- memmove(ec_dev->din, ptr, todo);
- ptr = ec_dev->din + todo;
- dev_dbg(ec_dev->dev, "need %d, got %d bytes from preamble\n",
- need_len, todo);
- need_len -= todo;
-
- /* Receive data until we have it all */
- while (need_len > 0) {
- /*
- * We can't support transfers larger than the SPI FIFO size
- * unless we have DMA. We don't have DMA on the ISP SPI ports
- * for Exynos. We need a way of asking SPI driver for
- * maximum-supported transfer size.
- */
- todo = min(need_len, 256);
- dev_dbg(ec_dev->dev, "loop, todo=%d, need_len=%d, ptr=%zd\n",
- todo, need_len, ptr - ec_dev->din);
-
- ret = receive_n_bytes(ec_dev, ptr, todo);
- if (ret < 0)
- return ret;
-
- debug_packet(ec_dev->dev, "interim", ptr, todo);
- ptr += todo;
- need_len -= todo;
- }
-
- dev_dbg(ec_dev->dev, "loop done, ptr=%zd\n", ptr - ec_dev->din);
-
- return 0;
-}
-
-/**
- * cros_ec_pkt_xfer_spi - Transfer a packet over SPI and receive the reply
- *
- * @ec_dev: ChromeOS EC device
- * @ec_msg: Message to transfer
- */
-static int cros_ec_pkt_xfer_spi(struct cros_ec_device *ec_dev,
- struct cros_ec_command *ec_msg)
-{
- struct ec_host_response *response;
- struct cros_ec_spi *ec_spi = ec_dev->priv;
- struct spi_transfer trans, trans_delay;
- struct spi_message msg;
- int i, len;
- u8 *ptr;
- u8 *rx_buf;
- u8 sum;
- u8 rx_byte;
- int ret = 0, final_ret;
- unsigned long delay;
-
- len = cros_ec_prepare_tx(ec_dev, ec_msg);
- dev_dbg(ec_dev->dev, "prepared, len=%d\n", len);
-
- /* If it's too soon to do another transaction, wait */
- delay = ktime_get_ns() - ec_spi->last_transfer_ns;
- if (delay < EC_SPI_RECOVERY_TIME_NS)
- ndelay(EC_SPI_RECOVERY_TIME_NS - delay);
-
- rx_buf = kzalloc(len, GFP_KERNEL);
- if (!rx_buf)
- return -ENOMEM;
-
- spi_bus_lock(ec_spi->spi->master);
-
- /*
- * Leave a gap between CS assertion and clocking of data to allow the
- * EC time to wakeup.
- */
- spi_message_init(&msg);
- if (ec_spi->start_of_msg_delay) {
- memset(&trans_delay, 0, sizeof(trans_delay));
- trans_delay.delay_usecs = ec_spi->start_of_msg_delay;
- spi_message_add_tail(&trans_delay, &msg);
- }
-
- /* Transmit phase - send our message */
- memset(&trans, 0, sizeof(trans));
- trans.tx_buf = ec_dev->dout;
- trans.rx_buf = rx_buf;
- trans.len = len;
- trans.cs_change = 1;
- spi_message_add_tail(&trans, &msg);
- ret = spi_sync_locked(ec_spi->spi, &msg);
-
- /* Get the response */
- if (!ret) {
- /* Verify that EC can process command */
- for (i = 0; i < len; i++) {
- rx_byte = rx_buf[i];
- /*
- * Seeing the PAST_END, RX_BAD_DATA, or NOT_READY
- * markers are all signs that the EC didn't fully
- * receive our command. e.g., if the EC is flashing
- * itself, it can't respond to any commands and instead
- * clocks out EC_SPI_PAST_END from its SPI hardware
- * buffer. Similar occurrences can happen if the AP is
- * too slow to clock out data after asserting CS -- the
- * EC will abort and fill its buffer with
- * EC_SPI_RX_BAD_DATA.
- *
- * In all cases, these errors should be safe to retry.
- * Report -EAGAIN and let the caller decide what to do
- * about that.
- */
- if (rx_byte == EC_SPI_PAST_END ||
- rx_byte == EC_SPI_RX_BAD_DATA ||
- rx_byte == EC_SPI_NOT_READY) {
- ret = -EAGAIN;
- break;
- }
- }
- }
-
- if (!ret)
- ret = cros_ec_spi_receive_packet(ec_dev,
- ec_msg->insize + sizeof(*response));
- else if (ret != -EAGAIN)
- dev_err(ec_dev->dev, "spi transfer failed: %d\n", ret);
-
- final_ret = terminate_request(ec_dev);
-
- spi_bus_unlock(ec_spi->spi->master);
-
- if (!ret)
- ret = final_ret;
- if (ret < 0)
- goto exit;
-
- ptr = ec_dev->din;
-
- /* check response error code */
- response = (struct ec_host_response *)ptr;
- ec_msg->result = response->result;
-
- ret = cros_ec_check_result(ec_dev, ec_msg);
- if (ret)
- goto exit;
-
- len = response->data_len;
- sum = 0;
- if (len > ec_msg->insize) {
- dev_err(ec_dev->dev, "packet too long (%d bytes, expected %d)",
- len, ec_msg->insize);
- ret = -EMSGSIZE;
- goto exit;
- }
-
- for (i = 0; i < sizeof(*response); i++)
- sum += ptr[i];
-
- /* copy response packet payload and compute checksum */
- memcpy(ec_msg->data, ptr + sizeof(*response), len);
- for (i = 0; i < len; i++)
- sum += ec_msg->data[i];
-
- if (sum) {
- dev_err(ec_dev->dev,
- "bad packet checksum, calculated %x\n",
- sum);
- ret = -EBADMSG;
- goto exit;
- }
-
- ret = len;
-exit:
- kfree(rx_buf);
- if (ec_msg->command == EC_CMD_REBOOT_EC)
- msleep(EC_REBOOT_DELAY_MS);
-
- return ret;
-}
-
-/**
- * cros_ec_cmd_xfer_spi - Transfer a message over SPI and receive the reply
- *
- * @ec_dev: ChromeOS EC device
- * @ec_msg: Message to transfer
- */
-static int cros_ec_cmd_xfer_spi(struct cros_ec_device *ec_dev,
- struct cros_ec_command *ec_msg)
-{
- struct cros_ec_spi *ec_spi = ec_dev->priv;
- struct spi_transfer trans;
- struct spi_message msg;
- int i, len;
- u8 *ptr;
- u8 *rx_buf;
- u8 rx_byte;
- int sum;
- int ret = 0, final_ret;
- unsigned long delay;
-
- len = cros_ec_prepare_tx(ec_dev, ec_msg);
- dev_dbg(ec_dev->dev, "prepared, len=%d\n", len);
-
- /* If it's too soon to do another transaction, wait */
- delay = ktime_get_ns() - ec_spi->last_transfer_ns;
- if (delay < EC_SPI_RECOVERY_TIME_NS)
- ndelay(EC_SPI_RECOVERY_TIME_NS - delay);
-
- rx_buf = kzalloc(len, GFP_KERNEL);
- if (!rx_buf)
- return -ENOMEM;
-
- spi_bus_lock(ec_spi->spi->master);
-
- /* Transmit phase - send our message */
- debug_packet(ec_dev->dev, "out", ec_dev->dout, len);
- memset(&trans, 0, sizeof(trans));
- trans.tx_buf = ec_dev->dout;
- trans.rx_buf = rx_buf;
- trans.len = len;
- trans.cs_change = 1;
- spi_message_init(&msg);
- spi_message_add_tail(&trans, &msg);
- ret = spi_sync_locked(ec_spi->spi, &msg);
-
- /* Get the response */
- if (!ret) {
- /* Verify that EC can process command */
- for (i = 0; i < len; i++) {
- rx_byte = rx_buf[i];
- /* See comments in cros_ec_pkt_xfer_spi() */
- if (rx_byte == EC_SPI_PAST_END ||
- rx_byte == EC_SPI_RX_BAD_DATA ||
- rx_byte == EC_SPI_NOT_READY) {
- ret = -EAGAIN;
- break;
- }
- }
- }
-
- if (!ret)
- ret = cros_ec_spi_receive_response(ec_dev,
- ec_msg->insize + EC_MSG_TX_PROTO_BYTES);
- else if (ret != -EAGAIN)
- dev_err(ec_dev->dev, "spi transfer failed: %d\n", ret);
-
- final_ret = terminate_request(ec_dev);
-
- spi_bus_unlock(ec_spi->spi->master);
-
- if (!ret)
- ret = final_ret;
- if (ret < 0)
- goto exit;
-
- ptr = ec_dev->din;
-
- /* check response error code */
- ec_msg->result = ptr[0];
- ret = cros_ec_check_result(ec_dev, ec_msg);
- if (ret)
- goto exit;
-
- len = ptr[1];
- sum = ptr[0] + ptr[1];
- if (len > ec_msg->insize) {
- dev_err(ec_dev->dev, "packet too long (%d bytes, expected %d)",
- len, ec_msg->insize);
- ret = -ENOSPC;
- goto exit;
- }
-
- /* copy response packet payload and compute checksum */
- for (i = 0; i < len; i++) {
- sum += ptr[i + 2];
- if (ec_msg->insize)
- ec_msg->data[i] = ptr[i + 2];
- }
- sum &= 0xff;
-
- debug_packet(ec_dev->dev, "in", ptr, len + 3);
-
- if (sum != ptr[len + 2]) {
- dev_err(ec_dev->dev,
- "bad packet checksum, expected %02x, got %02x\n",
- sum, ptr[len + 2]);
- ret = -EBADMSG;
- goto exit;
- }
-
- ret = len;
-exit:
- kfree(rx_buf);
- if (ec_msg->command == EC_CMD_REBOOT_EC)
- msleep(EC_REBOOT_DELAY_MS);
-
- return ret;
-}
-
-static void cros_ec_spi_dt_probe(struct cros_ec_spi *ec_spi, struct device *dev)
-{
- struct device_node *np = dev->of_node;
- u32 val;
- int ret;
-
- ret = of_property_read_u32(np, "google,cros-ec-spi-pre-delay", &val);
- if (!ret)
- ec_spi->start_of_msg_delay = val;
-
- ret = of_property_read_u32(np, "google,cros-ec-spi-msg-delay", &val);
- if (!ret)
- ec_spi->end_of_msg_delay = val;
-}
-
-static int cros_ec_spi_probe(struct spi_device *spi)
-{
- struct device *dev = &spi->dev;
- struct cros_ec_device *ec_dev;
- struct cros_ec_spi *ec_spi;
- int err;
-
- spi->bits_per_word = 8;
- spi->mode = SPI_MODE_0;
- err = spi_setup(spi);
- if (err < 0)
- return err;
-
- ec_spi = devm_kzalloc(dev, sizeof(*ec_spi), GFP_KERNEL);
- if (ec_spi == NULL)
- return -ENOMEM;
- ec_spi->spi = spi;
- ec_dev = devm_kzalloc(dev, sizeof(*ec_dev), GFP_KERNEL);
- if (!ec_dev)
- return -ENOMEM;
-
- /* Check for any DT properties */
- cros_ec_spi_dt_probe(ec_spi, dev);
-
- spi_set_drvdata(spi, ec_dev);
- ec_dev->dev = dev;
- ec_dev->priv = ec_spi;
- ec_dev->irq = spi->irq;
- ec_dev->cmd_xfer = cros_ec_cmd_xfer_spi;
- ec_dev->pkt_xfer = cros_ec_pkt_xfer_spi;
- ec_dev->phys_name = dev_name(&ec_spi->spi->dev);
- ec_dev->din_size = EC_MSG_PREAMBLE_COUNT +
- sizeof(struct ec_host_response) +
- sizeof(struct ec_response_get_protocol_info);
- ec_dev->dout_size = sizeof(struct ec_host_request);
-
- ec_spi->last_transfer_ns = ktime_get_ns();
-
- err = cros_ec_register(ec_dev);
- if (err) {
- dev_err(dev, "cannot register EC\n");
- return err;
- }
-
- device_init_wakeup(&spi->dev, true);
-
- return 0;
-}
-
-static int cros_ec_spi_remove(struct spi_device *spi)
-{
- struct cros_ec_device *ec_dev;
-
- ec_dev = spi_get_drvdata(spi);
- cros_ec_remove(ec_dev);
-
- return 0;
-}
-
-#ifdef CONFIG_PM_SLEEP
-static int cros_ec_spi_suspend(struct device *dev)
-{
- struct cros_ec_device *ec_dev = dev_get_drvdata(dev);
-
- return cros_ec_suspend(ec_dev);
-}
-
-static int cros_ec_spi_resume(struct device *dev)
-{
- struct cros_ec_device *ec_dev = dev_get_drvdata(dev);
-
- return cros_ec_resume(ec_dev);
-}
-#endif
-
-static SIMPLE_DEV_PM_OPS(cros_ec_spi_pm_ops, cros_ec_spi_suspend,
- cros_ec_spi_resume);
-
-static const struct of_device_id cros_ec_spi_of_match[] = {
- { .compatible = "google,cros-ec-spi", },
- { /* sentinel */ },
-};
-MODULE_DEVICE_TABLE(of, cros_ec_spi_of_match);
-
-static const struct spi_device_id cros_ec_spi_id[] = {
- { "cros-ec-spi", 0 },
- { }
-};
-MODULE_DEVICE_TABLE(spi, cros_ec_spi_id);
-
-static struct spi_driver cros_ec_driver_spi = {
- .driver = {
- .name = "cros-ec-spi",
- .of_match_table = of_match_ptr(cros_ec_spi_of_match),
- .pm = &cros_ec_spi_pm_ops,
- },
- .probe = cros_ec_spi_probe,
- .remove = cros_ec_spi_remove,
- .id_table = cros_ec_spi_id,
-};
-
-module_spi_driver(cros_ec_driver_spi);
-
-MODULE_LICENSE("GPL v2");
-MODULE_DESCRIPTION("ChromeOS EC multi function device (SPI)");
projects / linux-2.6-microblaze.git / blobdiff