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Message-ID: <CAMHSBOXasZkTbQ1km_xxQrUz1q+UaGC1bWmizTFfTvtgvdk=rA@mail.gmail.com>
Date: Sat, 25 Apr 2015 18:39:50 -0700
From: Gwendal Grignou <gwendal@...omium.org>
To: Javier Martinez Canillas <javier.martinez@...labora.co.uk>
Cc: Olof Johansson <olof@...om.net>, Lee Jones <lee.jones@...aro.org>,
Doug Anderson <dianders@...omium.org>,
Bill Richardson <wfrichar@...omium.org>,
Simon Glass <sjg@...gle.com>,
Stephen Barber <smbarber@...omium.org>,
Filipe Brandenburger <filbranden@...gle.com>,
Todd Broch <tbroch@...omium.org>,
linux-samsung-soc@...r.kernel.org,
Linux Kernel <linux-kernel@...r.kernel.org>
Subject: Re: [RESEND PATCH 8/8] mfd: cros_ec: add bus-specific proto v3 code
Reviewed-by: Gwendal Grignou <gwendal@...omium.org>
Tested-by: Gwendal Grignou <gwendal@...omium.org>
On Mon, Apr 6, 2015 at 9:15 AM, Javier Martinez Canillas
<javier.martinez@...labora.co.uk> wrote:
> From: Stephen Barber <smbarber@...omium.org>
>
> Add proto v3 support to the SPI, I2C, and LPC.
>
> Signed-off-by: Stephen Barber <smbarber@...omium.org>
> Signed-off-by: Javier Martinez Canillas <javier.martinez@...labora.co.uk>
> ---
> drivers/mfd/cros_ec_i2c.c | 166 ++++++++++++++-
> drivers/mfd/cros_ec_spi.c | 382 +++++++++++++++++++++++++++++-----
> drivers/platform/chrome/cros_ec_lpc.c | 73 ++++++-
> include/linux/mfd/cros_ec.h | 6 +
> 4 files changed, 569 insertions(+), 58 deletions(-)
>
> diff --git a/drivers/mfd/cros_ec_i2c.c b/drivers/mfd/cros_ec_i2c.c
> index b400bfa2772a..22e8a4ae1711 100644
> --- a/drivers/mfd/cros_ec_i2c.c
> +++ b/drivers/mfd/cros_ec_i2c.c
> @@ -13,6 +13,7 @@
> * GNU General Public License for more details.
> */
>
> +#include <linux/delay.h>
> #include <linux/kernel.h>
> #include <linux/module.h>
> #include <linux/i2c.h>
> @@ -22,6 +23,32 @@
> #include <linux/platform_device.h>
> #include <linux/slab.h>
>
> +/**
> + * Request format for protocol v3
> + * byte 0 0xda (EC_COMMAND_PROTOCOL_3)
> + * byte 1-8 struct ec_host_request
> + * byte 10- response data
> + */
> +struct ec_host_request_i2c {
> + /* Always 0xda to backward compatible with v2 struct */
> + uint8_t command_protocol;
> + struct ec_host_request ec_request;
> +} __packed;
> +
> +
> +/*
> + * Response format for protocol v3
> + * byte 0 result code
> + * byte 1 packet_length
> + * byte 2-9 struct ec_host_response
> + * byte 10- response data
> + */
> +struct ec_host_response_i2c {
> + uint8_t result;
> + uint8_t packet_length;
> + struct ec_host_response ec_response;
> +} __packed;
> +
> static inline struct cros_ec_device *to_ec_dev(struct device *dev)
> {
> struct i2c_client *client = to_i2c_client(dev);
> @@ -29,6 +56,134 @@ static inline struct cros_ec_device *to_ec_dev(struct device *dev)
> return i2c_get_clientdata(client);
> }
>
> +static int cros_ec_pkt_xfer_i2c(struct cros_ec_device *ec_dev,
> + struct cros_ec_command *msg)
> +{
> + struct i2c_client *client = ec_dev->priv;
> + int ret = -ENOMEM;
> + int i;
> + int packet_len;
> + u8 *out_buf = NULL;
> + u8 *in_buf = NULL;
> + u8 sum;
> + struct i2c_msg i2c_msg[2];
> + struct ec_host_response *ec_response;
> + struct ec_host_request_i2c *ec_request_i2c;
> + struct ec_host_response_i2c *ec_response_i2c;
> + int request_header_size = sizeof(struct ec_host_request_i2c);
> + int response_header_size = sizeof(struct ec_host_response_i2c);
> +
> + i2c_msg[0].addr = client->addr;
> + i2c_msg[0].flags = 0;
> + i2c_msg[1].addr = client->addr;
> + i2c_msg[1].flags = I2C_M_RD;
> +
> + packet_len = msg->insize + response_header_size;
> + BUG_ON(packet_len > ec_dev->din_size);
> + in_buf = ec_dev->din;
> + i2c_msg[1].len = packet_len;
> + i2c_msg[1].buf = (char *) in_buf;
> +
> + packet_len = msg->outsize + request_header_size;
> + BUG_ON(packet_len > ec_dev->dout_size);
> + out_buf = ec_dev->dout;
> + i2c_msg[0].len = packet_len;
> + i2c_msg[0].buf = (char *) out_buf;
> +
> + /* create request data */
> + ec_request_i2c = (struct ec_host_request_i2c *) out_buf;
> + ec_request_i2c->command_protocol = EC_COMMAND_PROTOCOL_3;
> +
> + ec_dev->dout++;
> + ret = cros_ec_prepare_tx(ec_dev, msg);
> + ec_dev->dout--;
> +
> + /* send command to EC and read answer */
> + ret = i2c_transfer(client->adapter, i2c_msg, 2);
> + if (ret < 0) {
> + dev_dbg(ec_dev->dev, "i2c transfer failed: %d\n", ret);
> + goto done;
> + } else if (ret != 2) {
> + dev_err(ec_dev->dev, "failed to get response: %d\n", ret);
> + ret = -EIO;
> + goto done;
> + }
> +
> + ec_response_i2c = (struct ec_host_response_i2c *) in_buf;
> + msg->result = ec_response_i2c->result;
> + ec_response = &ec_response_i2c->ec_response;
> +
> + switch (msg->result) {
> + case EC_RES_SUCCESS:
> + break;
> + case EC_RES_IN_PROGRESS:
> + ret = -EAGAIN;
> + dev_dbg(ec_dev->dev, "command 0x%02x in progress\n",
> + msg->command);
> + goto done;
> +
> + default:
> + dev_dbg(ec_dev->dev, "command 0x%02x returned %d\n",
> + msg->command, msg->result);
> + /*
> + * When we send v3 request to v2 ec, ec won't recognize the
> + * 0xda (EC_COMMAND_PROTOCOL_3) and will return with status
> + * EC_RES_INVALID_COMMAND with zero data length.
> + *
> + * In case of invalid command for v3 protocol the data length
> + * will be at least sizeof(struct ec_host_response)
> + */
> + if (ec_response_i2c->result == EC_RES_INVALID_COMMAND &&
> + ec_response_i2c->packet_length == 0) {
> + ret = -EPROTONOSUPPORT;
> + goto done;
> + }
> + }
> +
> + if (ec_response_i2c->packet_length < sizeof(struct ec_host_response)) {
> + dev_err(ec_dev->dev,
> + "response of %u bytes too short; not a full header\n",
> + ec_response_i2c->packet_length);
> + ret = -EBADMSG;
> + goto done;
> + }
> +
> + if (msg->insize < ec_response->data_len) {
> + dev_err(ec_dev->dev,
> + "response data size is too large: expected %u, got %u\n",
> + msg->insize,
> + ec_response->data_len);
> + ret = -EMSGSIZE;
> + goto done;
> + }
> +
> + /* copy response packet payload and compute checksum */
> + sum = 0;
> + for (i = 0; i < sizeof(struct ec_host_response); i++)
> + sum += ((u8 *)ec_response)[i];
> +
> + memcpy(msg->data,
> + in_buf + response_header_size,
> + ec_response->data_len);
> + for (i = 0; i < ec_response->data_len; i++)
> + sum += msg->data[i];
> +
> + /* All bytes should sum to zero */
> + if (sum) {
> + dev_err(ec_dev->dev, "bad packet checksum\n");
> + ret = -EBADMSG;
> + goto done;
> + }
> +
> + ret = ec_response->data_len;
> +
> +done:
> + if (msg->command == EC_CMD_REBOOT_EC)
> + msleep(EC_REBOOT_DELAY_MS);
> +
> + return ret;
> +}
> +
> static int cros_ec_cmd_xfer_i2c(struct cros_ec_device *ec_dev,
> struct cros_ec_command *msg)
> {
> @@ -121,9 +276,12 @@ static int cros_ec_cmd_xfer_i2c(struct cros_ec_device *ec_dev,
> }
>
> ret = len;
> - done:
> +done:
> kfree(in_buf);
> kfree(out_buf);
> + if (msg->command == EC_CMD_REBOOT_EC)
> + msleep(EC_REBOOT_DELAY_MS);
> +
> return ret;
> }
>
> @@ -143,12 +301,12 @@ static int cros_ec_i2c_probe(struct i2c_client *client,
> ec_dev->priv = client;
> ec_dev->irq = client->irq;
> ec_dev->cmd_xfer = cros_ec_cmd_xfer_i2c;
> - ec_dev->pkt_xfer = NULL;
> + ec_dev->pkt_xfer = cros_ec_pkt_xfer_i2c;
> ec_dev->ec_name = client->name;
> ec_dev->phys_name = client->adapter->name;
> - ec_dev->din_size = sizeof(struct ec_host_response) +
> + ec_dev->din_size = sizeof(struct ec_host_response_i2c) +
> sizeof(struct ec_response_get_protocol_info);
> - ec_dev->dout_size = sizeof(struct ec_host_request);
> + ec_dev->dout_size = sizeof(struct ec_host_request_i2c);
>
> err = cros_ec_register(ec_dev);
> if (err) {
> diff --git a/drivers/mfd/cros_ec_spi.c b/drivers/mfd/cros_ec_spi.c
> index 04da2f288ef8..4e6f2f6b1095 100644
> --- a/drivers/mfd/cros_ec_spi.c
> +++ b/drivers/mfd/cros_ec_spi.c
> @@ -65,12 +65,6 @@
> */
> #define EC_SPI_RECOVERY_TIME_NS (200 * 1000)
>
> -/*
> - * The EC is unresponsive for a time after a reboot command. Add a
> - * simple delay to make sure that the bus stays locked.
> - */
> -#define EC_REBOOT_DELAY_MS 50
> -
> /**
> * struct cros_ec_spi - information about a SPI-connected EC
> *
> @@ -87,7 +81,7 @@ struct cros_ec_spi {
> };
>
> static void debug_packet(struct device *dev, const char *name, u8 *ptr,
> - int len)
> + int len)
> {
> #ifdef DEBUG
> int i;
> @@ -100,6 +94,172 @@ static void debug_packet(struct device *dev, const char *name, u8 *ptr,
> #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(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(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_MSG_PREAMBLE_COUNT > ec_dev->din_size);
> +
> + /* 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.
> *
> @@ -115,34 +275,27 @@ static void debug_packet(struct device *dev, const char *name, u8 *ptr,
> static int cros_ec_spi_receive_response(struct cros_ec_device *ec_dev,
> int need_len)
> {
> - struct cros_ec_spi *ec_spi = ec_dev->priv;
> - struct spi_transfer trans;
> - struct spi_message msg;
> u8 *ptr, *end;
> int ret;
> unsigned long deadline;
> int todo;
>
> + BUG_ON(EC_MSG_PREAMBLE_COUNT > ec_dev->din_size);
> +
> /* Receive data until we see the header byte */
> deadline = jiffies + msecs_to_jiffies(EC_MSG_DEADLINE_MS);
> while (true) {
> unsigned long start_jiffies = jiffies;
>
> - memset(&trans, 0, sizeof(trans));
> - trans.cs_change = 1;
> - trans.rx_buf = ptr = ec_dev->din;
> - trans.len = EC_MSG_PREAMBLE_COUNT;
> -
> - spi_message_init(&msg);
> - spi_message_add_tail(&trans, &msg);
> - ret = spi_sync(ec_spi->spi, &msg);
> - if (ret < 0) {
> - dev_err(ec_dev->dev, "spi transfer failed: %d\n", ret);
> + 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_MSG_HEADER) {
> + if (*ptr == EC_SPI_FRAME_START) {
> dev_dbg(ec_dev->dev, "msg found at %zd\n",
> ptr - ec_dev->din);
> break;
> @@ -187,21 +340,9 @@ static int cros_ec_spi_receive_response(struct cros_ec_device *ec_dev,
> dev_dbg(ec_dev->dev, "loop, todo=%d, need_len=%d, ptr=%zd\n",
> todo, need_len, ptr - ec_dev->din);
>
> - memset(&trans, 0, sizeof(trans));
> - trans.cs_change = 1;
> - trans.rx_buf = ptr;
> - trans.len = todo;
> - spi_message_init(&msg);
> - spi_message_add_tail(&trans, &msg);
> -
> - /* send command to EC and read answer */
> - BUG_ON((u8 *)trans.rx_buf - ec_dev->din + todo >
> - ec_dev->din_size);
> - ret = spi_sync(ec_spi->spi, &msg);
> - if (ret < 0) {
> - dev_err(ec_dev->dev, "spi transfer failed: %d\n", ret);
> + ret = receive_n_bytes(ec_dev, ptr, todo);
> + if (ret < 0)
> return ret;
> - }
>
> debug_packet(ec_dev->dev, "interim", ptr, todo);
> ptr += todo;
> @@ -214,6 +355,128 @@ static int cros_ec_spi_receive_response(struct cros_ec_device *ec_dev,
> }
>
> /**
> + * 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_request *request;
> + struct ec_host_response *response;
> + 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 sum;
> + int ret = 0, final_ret;
> +
> + len = cros_ec_prepare_tx(ec_dev, ec_msg);
> + request = (struct ec_host_request *)ec_dev->dout;
> + dev_dbg(ec_dev->dev, "prepared, len=%d\n", len);
> +
> + /* If it's too soon to do another transaction, wait */
> + if (ec_spi->last_transfer_ns) {
> + unsigned long delay; /* The delay completed so far */
> +
> + 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) {
> + ret = -ENOMEM;
> + goto exit;
> + }
> +
> + /* 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_init(&msg);
> + spi_message_add_tail(&trans, &msg);
> + ret = spi_sync(ec_spi->spi, &msg);
> +
> + /* Get the response */
> + if (!ret) {
> + /* Verify that EC can process command */
> + for (i = 0; i < len; i++) {
> + switch (rx_buf[i]) {
> + case EC_SPI_PAST_END:
> + case EC_SPI_RX_BAD_DATA:
> + case EC_SPI_NOT_READY:
> + ret = -EAGAIN;
> + ec_msg->result = EC_RES_IN_PROGRESS;
> + default:
> + break;
> + }
> + if (ret)
> + break;
> + }
> + if (!ret)
> + ret = cros_ec_spi_receive_packet(ec_dev,
> + ec_msg->insize + sizeof(*response));
> + } else {
> + dev_err(ec_dev->dev, "spi transfer failed: %d\n", ret);
> + }
> +
> + final_ret = terminate_request(ec_dev);
> + 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
> @@ -227,6 +490,7 @@ static int cros_ec_cmd_xfer_spi(struct cros_ec_device *ec_dev,
> struct spi_message msg;
> int i, len;
> u8 *ptr;
> + u8 *rx_buf;
> int sum;
> int ret = 0, final_ret;
>
> @@ -242,10 +506,17 @@ static int cros_ec_cmd_xfer_spi(struct cros_ec_device *ec_dev,
> ndelay(EC_SPI_RECOVERY_TIME_NS - delay);
> }
>
> + rx_buf = kzalloc(len, GFP_KERNEL);
> + if (!rx_buf) {
> + ret = -ENOMEM;
> + goto exit;
> + }
> +
> /* 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);
> @@ -254,29 +525,32 @@ static int cros_ec_cmd_xfer_spi(struct cros_ec_device *ec_dev,
>
> /* Get the response */
> if (!ret) {
> - ret = cros_ec_spi_receive_response(ec_dev,
> - ec_msg->insize + EC_MSG_TX_PROTO_BYTES);
> + /* Verify that EC can process command */
> + for (i = 0; i < len; i++) {
> + switch (rx_buf[i]) {
> + case EC_SPI_PAST_END:
> + case EC_SPI_RX_BAD_DATA:
> + case EC_SPI_NOT_READY:
> + ret = -EAGAIN;
> + ec_msg->result = EC_RES_IN_PROGRESS;
> + default:
> + break;
> + }
> + if (ret)
> + break;
> + }
> + if (!ret)
> + ret = cros_ec_spi_receive_response(ec_dev,
> + ec_msg->insize + EC_MSG_TX_PROTO_BYTES);
> } else {
> dev_err(ec_dev->dev, "spi transfer failed: %d\n", 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);
> -
> - final_ret = spi_sync(ec_spi->spi, &msg);
> - ec_spi->last_transfer_ns = ktime_get_ns();
> + final_ret = terminate_request(ec_dev);
> if (!ret)
> ret = final_ret;
> - if (ret < 0) {
> - dev_err(ec_dev->dev, "spi transfer failed: %d\n", ret);
> + if (ret < 0)
> goto exit;
> - }
>
> ptr = ec_dev->din;
>
> @@ -315,6 +589,7 @@ static int cros_ec_cmd_xfer_spi(struct cros_ec_device *ec_dev,
>
> ret = len;
> exit:
> + kfree(rx_buf);
> if (ec_msg->command == EC_CMD_REBOOT_EC)
> msleep(EC_REBOOT_DELAY_MS);
>
> @@ -361,7 +636,7 @@ static int cros_ec_spi_probe(struct spi_device *spi)
> ec_dev->priv = ec_spi;
> ec_dev->irq = spi->irq;
> ec_dev->cmd_xfer = cros_ec_cmd_xfer_spi;
> - ec_dev->pkt_xfer = NULL;
> + ec_dev->pkt_xfer = cros_ec_pkt_xfer_spi;
> ec_dev->ec_name = ec_spi->spi->modalias;
> ec_dev->phys_name = dev_name(&ec_spi->spi->dev);
> ec_dev->din_size = EC_MSG_PREAMBLE_COUNT +
> @@ -369,6 +644,7 @@ static int cros_ec_spi_probe(struct spi_device *spi)
> sizeof(struct ec_response_get_protocol_info);
> ec_dev->dout_size = sizeof(struct ec_host_request);
>
> +
> err = cros_ec_register(ec_dev);
> if (err) {
> dev_err(dev, "cannot register EC\n");
> diff --git a/drivers/platform/chrome/cros_ec_lpc.c b/drivers/platform/chrome/cros_ec_lpc.c
> index d56dfb9dd463..e98b0345288a 100644
> --- a/drivers/platform/chrome/cros_ec_lpc.c
> +++ b/drivers/platform/chrome/cros_ec_lpc.c
> @@ -46,6 +46,77 @@ static int ec_response_timed_out(void)
> return 1;
> }
>
> +static int cros_ec_pkt_xfer_lpc(struct cros_ec_device *ec,
> + struct cros_ec_command *msg)
> +{
> + struct ec_host_request *request;
> + struct ec_host_response response;
> + u8 sum = 0;
> + int i;
> + int ret = 0;
> + u8 *dout;
> +
> + ret = cros_ec_prepare_tx(ec, msg);
> +
> + /* Write buffer */
> + for (i = 0; i < ret; i++)
> + outb(ec->dout[i], EC_LPC_ADDR_HOST_PACKET + i);
> +
> + request = (struct ec_host_request *)ec->dout;
> +
> + /* Here we go */
> + outb(EC_COMMAND_PROTOCOL_3, EC_LPC_ADDR_HOST_CMD);
> +
> + if (ec_response_timed_out()) {
> + dev_warn(ec->dev, "EC responsed timed out\n");
> + ret = -EIO;
> + goto done;
> + }
> +
> + /* Check result */
> + msg->result = inb(EC_LPC_ADDR_HOST_DATA);
> + ret = cros_ec_check_result(ec, msg);
> + if (ret)
> + goto done;
> +
> + /* Read back response */
> + dout = (u8 *)&response;
> + for (i = 0; i < sizeof(response); i++) {
> + dout[i] = inb(EC_LPC_ADDR_HOST_PACKET + i);
> + sum += dout[i];
> + }
> +
> + msg->result = response.result;
> +
> + if (response.data_len > msg->insize) {
> + dev_err(ec->dev,
> + "packet too long (%d bytes, expected %d)",
> + response.data_len, msg->insize);
> + ret = -EMSGSIZE;
> + goto done;
> + }
> +
> + /* Read response and process checksum */
> + for (i = 0; i < response.data_len; i++) {
> + msg->data[i] =
> + inb(EC_LPC_ADDR_HOST_PACKET + sizeof(response) + i);
> + sum += msg->data[i];
> + }
> +
> + if (sum) {
> + dev_err(ec->dev,
> + "bad packet checksum %02x\n",
> + response.checksum);
> + ret = -EBADMSG;
> + goto done;
> + }
> +
> + /* Return actual amount of data received */
> + ret = response.data_len;
> +done:
> + return ret;
> +}
> +
> static int cros_ec_cmd_xfer_lpc(struct cros_ec_device *ec,
> struct cros_ec_command *msg)
> {
> @@ -205,7 +276,7 @@ static int cros_ec_lpc_probe(struct platform_device *pdev)
> ec_dev->ec_name = pdev->name;
> ec_dev->phys_name = dev_name(dev);
> ec_dev->cmd_xfer = cros_ec_cmd_xfer_lpc;
> - ec_dev->pkt_xfer = NULL;
> + ec_dev->pkt_xfer = cros_ec_pkt_xfer_lpc;
> ec_dev->cmd_readmem = cros_ec_lpc_readmem;
> ec_dev->din_size = sizeof(struct ec_host_response) +
> sizeof(struct ec_response_get_protocol_info);
> diff --git a/include/linux/mfd/cros_ec.h b/include/linux/mfd/cros_ec.h
> index f27ce4b7736b..7a201caa60c8 100644
> --- a/include/linux/mfd/cros_ec.h
> +++ b/include/linux/mfd/cros_ec.h
> @@ -22,6 +22,12 @@
> #include <linux/mutex.h>
>
> /*
> + * The EC is unresponsive for a time after a reboot command. Add a
> + * simple delay to make sure that the bus stays locked.
> + */
> +#define EC_REBOOT_DELAY_MS 50
> +
> +/*
> * Max bus-specific overhead incurred by request/responses.
> * I2C requires 1 additional byte for requests.
> * I2C requires 2 additional bytes for responses.
> --
> 2.1.4
>
--
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