* [PATCH 1/2] cros: platform/chrome: Add cros-ec-uart driver for uart support
@ 2020-06-25 21:34 Bhanu Prakash Maiya
2020-06-25 21:34 ` [PATCH 2/2] dt-bindings: mfd: Add DT compatible string "google,cros_ec_uart" Bhanu Prakash Maiya
` (2 more replies)
0 siblings, 3 replies; 8+ messages in thread
From: Bhanu Prakash Maiya @ 2020-06-25 21:34 UTC (permalink / raw)
To: linux-arm-kernel
Cc: Benson Leung, Enric Balletbo i Serra, Guenter Roeck,
linux-kernel, Lee Jones ),
Rob Herring, Raul E Rangel, Furquan Shaikh, Duncan Laurie,
Eric Peers, devicetree, Bhanu Prakash Maiya
This patch enables uart transport layer for cros_ec framework.
The cros-ec-uart binds with EC device working on uart transport to
send request and receive response.
Signed-off-by: Bhanu Prakash Maiya <bhanumaiya@google.com>
---
MAINTAINERS | 1 +
drivers/platform/chrome/Kconfig | 10 +
drivers/platform/chrome/Makefile | 1 +
drivers/platform/chrome/cros_ec_uart.c | 399 +++++++++++++++++++++++++
4 files changed, 411 insertions(+)
create mode 100644 drivers/platform/chrome/cros_ec_uart.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 7b5ffd646c6b9..d4a089673429a 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4095,6 +4095,7 @@ F: sound/soc/codecs/cros_ec_codec.*
CHROMEOS EC SUBDRIVERS
M: Benson Leung <bleung@chromium.org>
M: Enric Balletbo i Serra <enric.balletbo@collabora.com>
+M: Bhanu Prakash Maiya <bhanumaiya@chromium.org>
R: Guenter Roeck <groeck@chromium.org>
S: Maintained
F: drivers/power/supply/cros_usbpd-charger.c
diff --git a/drivers/platform/chrome/Kconfig b/drivers/platform/chrome/Kconfig
index cf072153bdc5d..88b1b7b277ba3 100644
--- a/drivers/platform/chrome/Kconfig
+++ b/drivers/platform/chrome/Kconfig
@@ -118,6 +118,16 @@ config CROS_EC_SPI
response time cannot be guaranteed, we support ignoring
'pre-amble' bytes before the response actually starts.
+config CROS_EC_UART
+ tristate "ChromeOS Embedded Controller (UART)"
+ depends on CROS_EC && ACPI && SERIAL_DEV_BUS
+ help
+ If you say Y here, you get support for talking to the ChromeOS EC
+ through a UART, using a byte-level protocol.
+
+ To compile this driver as a module, choose M here: the
+ module will be called cros_ec_uart.
+
config CROS_EC_LPC
tristate "ChromeOS Embedded Controller (LPC)"
depends on CROS_EC && ACPI && (X86 || COMPILE_TEST)
diff --git a/drivers/platform/chrome/Makefile b/drivers/platform/chrome/Makefile
index 41baccba033f7..47d8d0f890ca2 100644
--- a/drivers/platform/chrome/Makefile
+++ b/drivers/platform/chrome/Makefile
@@ -11,6 +11,7 @@ obj-$(CONFIG_CROS_EC_I2C) += cros_ec_i2c.o
obj-$(CONFIG_CROS_EC_ISHTP) += cros_ec_ishtp.o
obj-$(CONFIG_CROS_EC_RPMSG) += cros_ec_rpmsg.o
obj-$(CONFIG_CROS_EC_SPI) += cros_ec_spi.o
+obj-$(CONFIG_CROS_EC_UART) += cros_ec_uart.o
cros_ec_lpcs-objs := cros_ec_lpc.o cros_ec_lpc_mec.o
obj-$(CONFIG_CROS_EC_TYPEC) += cros_ec_typec.o
obj-$(CONFIG_CROS_EC_LPC) += cros_ec_lpcs.o
diff --git a/drivers/platform/chrome/cros_ec_uart.c b/drivers/platform/chrome/cros_ec_uart.c
new file mode 100644
index 0000000000000..fe17c2a28b6ef
--- /dev/null
+++ b/drivers/platform/chrome/cros_ec_uart.c
@@ -0,0 +1,399 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * UART interface for ChromeOS Embedded Controller
+ *
+ * Copyright 2020 Google LLC.
+ */
+
+#include <linux/delay.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/acpi.h>
+#include <linux/of.h>
+#include <linux/platform_data/cros_ec_commands.h>
+#include <linux/platform_data/cros_ec_proto.h>
+#include <linux/platform_device.h>
+#include <linux/serdev.h>
+#include <linux/slab.h>
+#include <uapi/linux/sched/types.h>
+
+/*
+ * Allow for a long time for EC to respond.
+ */
+#define EC_MSG_DEADLINE_MS 200
+
+/**
+ * struct response_info - Encapsulate EC response related
+ * information for passing between function
+ * cros_ec_uart_pkt_xfer() and cros_ec_uart_rx_bytes()
+ * callback.
+ * @data: Copy the data received from EC here.
+ * @max_size: Max size allocated for the @data buffer. If the
+ * received data exceeds this value, we log an error.
+ * @size: Actual size of data received from EC. This is also
+ * used to accumulate byte count with response is received
+ * in dma chunks.
+ * @exp_len: Expected bytes of response from EC.
+ * @error: 0 for success, negative error code for a failure.
+ * @received: Set to true on receiving a valid EC response.
+ * @wait_queue: Wait queue EC response where the cros_ec sends request
+ * to EC and waits
+ */
+struct response_info {
+ void *data;
+ size_t max_size;
+ size_t size;
+ int error;
+ size_t exp_len;
+ bool received;
+ wait_queue_head_t wait_queue;
+};
+
+/**
+ * struct cros_ec_uart - information about a uart-connected EC
+ *
+ * @serdev_device: serdev uart device we are connected to.
+ * @baudrate: UART baudrate of attached EC device.
+ * @flowcontrol: UART flowcontrol of attached device.
+ * @irq: Linux IRQ number of associated serial device.
+ * @response: Response info passing between cros_ec_uart_pkt_xfer()
+ * and cros_ec_uart_rx_bytes()
+ */
+struct cros_ec_uart {
+ struct serdev_device *serdev;
+ u32 baudrate;
+ u8 flowcontrol;
+ u32 irq;
+ struct response_info response;
+};
+
+static int cros_ec_uart_rx_bytes(struct serdev_device *serdev,
+ const u8 *data,
+ size_t count)
+{
+ struct ec_host_response *response;
+ struct cros_ec_device *ec_dev = serdev_device_get_drvdata(serdev);
+ struct cros_ec_uart *ec_uart = ec_dev->priv;
+
+ /* Check if bytes were sent out of band */
+ if (!ec_uart->response.data) {
+ /* Discard all bytes */
+ return count;
+ }
+
+ /*
+ * Check if incoming bytes + response.size are less than allocated
+ * buffer in din by cros_ec. This will ensure that if EC sends more
+ * bytes than max_size, waiting process will be notified with an error.
+ */
+ if (ec_uart->response.size + count <= ec_uart->response.max_size) {
+ /* Copy bytes in data in buffer */
+ memcpy((void *)ec_uart->response.data + ec_uart->response.size,
+ (void *)data, count);
+
+ /* Add incoming bytes in size */
+ ec_uart->response.size += count;
+
+ /*
+ * Read data_len if we received response header and if exp_len
+ * was not read before.
+ */
+ if (ec_uart->response.size >= sizeof(*response) &&
+ ec_uart->response.exp_len == 0) {
+ /* Get expected response length from response header */
+ response = (struct ec_host_response *)
+ ec_uart->response.data;
+
+ ec_uart->response.exp_len = response->data_len +
+ sizeof(*response);
+ }
+
+ /* Check if we received all response bytes from EC */
+ if (ec_uart->response.size >= ec_uart->response.exp_len) {
+ /* Set flag before waking up the caller */
+ ec_uart->response.received = true;
+
+ /* Wake the calling thread */
+ wake_up_interruptible(&ec_uart->response.wait_queue);
+ }
+ } else {
+ /* Received bytes are more the allocated buffer*/
+ ec_uart->response.error = -EMSGSIZE;
+
+ /* Wake the calling thread */
+ wake_up_interruptible(&ec_uart->response.wait_queue);
+ }
+
+ return count;
+}
+
+static int cros_ec_uart_pkt_xfer(struct cros_ec_device *ec_dev,
+ struct cros_ec_command *ec_msg)
+{
+ struct cros_ec_uart *ec_uart = ec_dev->priv;
+ struct serdev_device *serdev = ec_uart->serdev;
+ struct ec_host_response *response;
+ unsigned int len;
+ int ret, i;
+ u8 sum = 0;
+
+ /* Prepare an outgoing message in the output buffer */
+ len = cros_ec_prepare_tx(ec_dev, ec_msg);
+ dev_dbg(ec_dev->dev, "Prepared len=%d\n", len);
+
+ /* Setup for incoming response */
+ ec_uart->response.data = ec_dev->din;
+ ec_uart->response.max_size = ec_dev->din_size;
+ ec_uart->response.size = 0;
+ ec_uart->response.error = 0;
+ ec_uart->response.exp_len = 0;
+ ec_uart->response.received = false;
+
+ /* Write serial device buffer */
+ ret = serdev_device_write_buf(serdev, ec_dev->dout, len);
+ if (ret < len) {
+ dev_err(&serdev->dev,
+ "Unable to write data to serial device %s",
+ dev_name(&serdev->dev));
+
+ /* Return EIO as controller had issues writing buffer */
+ ret = -EIO;
+ goto exit;
+ }
+
+ /* Once request is successfully sent to EC, wait to wait_queue */
+ wait_event_interruptible_timeout(ec_uart->response.wait_queue,
+ ec_uart->response.received,
+ msecs_to_jiffies(EC_MSG_DEADLINE_MS));
+
+ /* Check if wait_queue was interrupted due to an error */
+ if (ec_uart->response.error < 0) {
+ dev_warn(&serdev->dev, "Response error detected.\n");
+
+ ret = ec_uart->response.error;
+ goto exit;
+ }
+
+ /* Check if valid response was received or there was a timeout */
+ if (!ec_uart->response.received) {
+ dev_warn(&serdev->dev, "EC failed to respond in time.\n");
+
+ ret = -ETIMEDOUT;
+ goto exit;
+ }
+
+ /* Check response error code */
+ response = (struct ec_host_response *)ec_dev->din;
+ ec_msg->result = response->result;
+
+ /* Check if received response is longer than expected */
+ if (response->data_len > ec_msg->insize) {
+ dev_err(ec_dev->dev, "Resp too long (%d bytes, expected %d)",
+ response->data_len,
+ ec_msg->insize);
+ ret = -ENOSPC;
+ goto exit;
+ }
+
+ /* Copy response packet to ec_msg data buffer */
+ memcpy(ec_msg->data,
+ ec_dev->din + sizeof(*response),
+ response->data_len);
+
+ /* Add all response header bytes for checksum calculation */
+ for (i = 0; i < sizeof(*response); i++)
+ sum += ec_dev->din[i];
+
+ /* Copy response packet payload and compute checksum */
+ for (i = 0; i < response->data_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;
+ }
+
+ /* Return data_len to cros_ec */
+ ret = response->data_len;
+
+exit:
+ /* Reset ec_uart */
+ ec_uart->response.data = NULL;
+ ec_uart->response.max_size = 0;
+ ec_uart->response.size = 0;
+ ec_uart->response.error = 0;
+ ec_uart->response.exp_len = 0;
+ ec_uart->response.received = false;
+
+ if (ec_msg->command == EC_CMD_REBOOT_EC)
+ msleep(EC_REBOOT_DELAY_MS);
+
+ return ret;
+}
+
+static int cros_ec_uart_resource(struct acpi_resource *ares, void *data)
+{
+ struct cros_ec_uart *ec_uart = data;
+ struct acpi_resource_uart_serialbus *sb;
+
+ switch (ares->type) {
+ case ACPI_RESOURCE_TYPE_SERIAL_BUS:
+ sb = &ares->data.uart_serial_bus;
+ if (sb->type == ACPI_RESOURCE_SERIAL_TYPE_UART) {
+ ec_uart->baudrate = sb->default_baud_rate;
+ dev_dbg(&ec_uart->serdev->dev, "Baudrate %d\n",
+ ec_uart->baudrate);
+
+ ec_uart->flowcontrol = sb->flow_control;
+ dev_dbg(&ec_uart->serdev->dev, "Flow control %d\n",
+ ec_uart->flowcontrol);
+ }
+ break;
+ default:
+ break;
+ }
+
+ return 0;
+}
+
+static int cros_ec_uart_acpi_probe(struct cros_ec_uart *ec_uart)
+{
+ LIST_HEAD(resources);
+ struct acpi_device *adev = ACPI_COMPANION(&ec_uart->serdev->dev);
+ int ret;
+
+ /* Retrieve UART ACPI info */
+ ret = acpi_dev_get_resources(adev, &resources,
+ cros_ec_uart_resource, ec_uart);
+ if (ret < 0)
+ return ret;
+
+ acpi_dev_free_resource_list(&resources);
+
+ /* Retrieve GpioInt and translate it to Linux IRQ number */
+ ret = acpi_dev_gpio_irq_get(adev, 0);
+ if (ret < 0)
+ return ret;
+
+ ec_uart->irq = ret;
+ dev_dbg(&ec_uart->serdev->dev, "IRQ number %d\n", ec_uart->irq);
+
+ return 0;
+}
+
+static const struct serdev_device_ops cros_ec_uart_client_ops = {
+ .receive_buf = cros_ec_uart_rx_bytes,
+};
+
+static int cros_ec_uart_probe(struct serdev_device *serdev)
+{
+ struct device *dev = &serdev->dev;
+ struct cros_ec_device *ec_dev;
+ struct cros_ec_uart *ec_uart;
+ int ret;
+
+ ec_uart = devm_kzalloc(dev, sizeof(*ec_uart), GFP_KERNEL);
+ if (!ec_uart)
+ return -ENOMEM;
+
+ ec_dev = devm_kzalloc(dev, sizeof(*ec_dev), GFP_KERNEL);
+ if (!ec_dev)
+ return -ENOMEM;
+
+ ec_uart->serdev = serdev;
+
+ /* Open the serial device */
+ ret = devm_serdev_device_open(dev, ec_uart->serdev);
+ if (ret) {
+ dev_err(dev, "Unable to open UART device %s",
+ dev_name(&serdev->dev));
+ return ret;
+ }
+
+ serdev_device_set_drvdata(serdev, ec_dev);
+
+ serdev_device_set_client_ops(serdev, &cros_ec_uart_client_ops);
+
+ /* Initialize wait queue */
+ init_waitqueue_head(&ec_uart->response.wait_queue);
+
+ ret = cros_ec_uart_acpi_probe(ec_uart);
+ if (ret < 0) {
+ dev_err(dev, "Failed to get ACPI info (%d)", ret);
+ return ret;
+ }
+
+ /* Set baud rate of serial device */
+ ret = serdev_device_set_baudrate(serdev, ec_uart->baudrate);
+ if (ret < 0) {
+ dev_err(dev, "Failed to set up host baud rate (%d)", ret);
+ return ret;
+ }
+
+ /* Set flow control of serial device */
+ serdev_device_set_flow_control(serdev, ec_uart->flowcontrol);
+
+ /* Initialize ec_dev for cros_ec */
+ ec_dev->phys_name = dev_name(&ec_uart->serdev->dev);
+ ec_dev->dev = dev;
+ ec_dev->priv = ec_uart;
+ ec_dev->irq = ec_uart->irq;
+ ec_dev->cmd_xfer = NULL;
+ ec_dev->pkt_xfer = cros_ec_uart_pkt_xfer;
+ ec_dev->din_size = sizeof(struct ec_host_response) +
+ sizeof(struct ec_response_get_protocol_info);
+ ec_dev->dout_size = sizeof(struct ec_host_request);
+
+ /* Register a new cros_ec device */
+ return cros_ec_register(ec_dev);
+}
+
+static void cros_ec_uart_remove(struct serdev_device *serdev)
+{
+ struct cros_ec_device *ec_dev = serdev_device_get_drvdata(serdev);
+
+ cros_ec_unregister(ec_dev);
+};
+
+static int __maybe_unused cros_ec_uart_suspend(struct device *dev)
+{
+ struct cros_ec_device *ec_dev = dev_get_drvdata(dev);
+
+ return cros_ec_suspend(ec_dev);
+}
+
+static int __maybe_unused cros_ec_uart_resume(struct device *dev)
+{
+ struct cros_ec_device *ec_dev = dev_get_drvdata(dev);
+
+ return cros_ec_resume(ec_dev);
+}
+
+static SIMPLE_DEV_PM_OPS(cros_ec_uart_pm_ops, cros_ec_uart_suspend,
+ cros_ec_uart_resume);
+
+static const struct of_device_id cros_ec_uart_of_match[] = {
+ { .compatible = "google,cros-ec-uart" },
+ {}
+};
+
+static struct serdev_device_driver cros_ec_uart_driver = {
+ .driver = {
+ .name = "cros-ec-uart",
+ .of_match_table = cros_ec_uart_of_match,
+ .pm = &cros_ec_uart_pm_ops,
+ },
+ .probe = cros_ec_uart_probe,
+ .remove = cros_ec_uart_remove,
+};
+
+module_serdev_device_driver(cros_ec_uart_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("UART interface for ChromeOS Embedded Controller");
+MODULE_AUTHOR("Bhanu Prakash Maiya <bhanumaiya@chromium.org>");
--
2.26.2
^ permalink raw reply related [flat|nested] 8+ messages in thread
* [PATCH 2/2] dt-bindings: mfd: Add DT compatible string "google,cros_ec_uart"
2020-06-25 21:34 [PATCH 1/2] cros: platform/chrome: Add cros-ec-uart driver for uart support Bhanu Prakash Maiya
@ 2020-06-25 21:34 ` Bhanu Prakash Maiya
2020-06-26 8:42 ` Enric Balletbo i Serra
2020-06-26 0:18 ` [PATCH 1/2] cros: platform/chrome: Add cros-ec-uart driver for uart support kernel test robot
2020-06-26 8:33 ` kernel test robot
2 siblings, 1 reply; 8+ messages in thread
From: Bhanu Prakash Maiya @ 2020-06-25 21:34 UTC (permalink / raw)
To: linux-arm-kernel
Cc: Benson Leung, Enric Balletbo i Serra, Guenter Roeck,
linux-kernel, Lee Jones ),
Rob Herring, Raul E Rangel, Furquan Shaikh, Duncan Laurie,
Eric Peers, devicetree, Bhanu Prakash Maiya
Add DT compatible string in
Documentation/devicetree/bindings/mfd/cros_ec.txt
Signed-off-by: Bhanu Prakash Maiya <bhanumaiya@google.com>
---
Documentation/devicetree/bindings/mfd/cros-ec.txt | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)
diff --git a/Documentation/devicetree/bindings/mfd/cros-ec.txt b/Documentation/devicetree/bindings/mfd/cros-ec.txt
index 4860eabd0f729..ec8c5d7ecc266 100644
--- a/Documentation/devicetree/bindings/mfd/cros-ec.txt
+++ b/Documentation/devicetree/bindings/mfd/cros-ec.txt
@@ -3,7 +3,7 @@ ChromeOS Embedded Controller
Google's ChromeOS EC is a Cortex-M device which talks to the AP and
implements various function such as keyboard and battery charging.
-The EC can be connect through various means (I2C, SPI, LPC, RPMSG) and the
+The EC can be connect through various means (I2C, SPI, UART, LPC, RPMSG) and the
compatible string used depends on the interface. Each connection method has
its own driver which connects to the top level interface-agnostic EC driver.
Other Linux driver (such as cros-ec-keyb for the matrix keyboard) connect to
@@ -17,6 +17,10 @@ Required properties (SPI):
- compatible: "google,cros-ec-spi"
- reg: SPI chip select
+Required properties (UART):
+- compatible: "google,cros-ec-uart"
+- reg: UART baudrate, flowcontrol
+
Required properties (RPMSG):
- compatible: "google,cros-ec-rpmsg"
@@ -72,5 +76,6 @@ spi@131b0000 {
};
};
-
Example for LPC is not supplied as it is not yet implemented.
+
+Example for UART is not supplied as it is not yet implemented.
--
2.26.2
^ permalink raw reply related [flat|nested] 8+ messages in thread
* Re: [PATCH 1/2] cros: platform/chrome: Add cros-ec-uart driver for uart support
2020-06-25 21:34 [PATCH 1/2] cros: platform/chrome: Add cros-ec-uart driver for uart support Bhanu Prakash Maiya
2020-06-25 21:34 ` [PATCH 2/2] dt-bindings: mfd: Add DT compatible string "google,cros_ec_uart" Bhanu Prakash Maiya
@ 2020-06-26 0:18 ` kernel test robot
2020-06-26 8:33 ` kernel test robot
2 siblings, 0 replies; 8+ messages in thread
From: kernel test robot @ 2020-06-26 0:18 UTC (permalink / raw)
To: Bhanu Prakash Maiya, linux-arm-kernel
Cc: kbuild-all, Benson Leung, Enric Balletbo i Serra, Guenter Roeck,
linux-kernel, Lee Jones ),
Rob Herring, Raul E Rangel, Furquan Shaikh, Duncan Laurie
[-- Attachment #1: Type: text/plain, Size: 5443 bytes --]
Hi Bhanu,
I love your patch! Yet something to improve:
[auto build test ERROR on chrome-platform-linux/for-next]
[also build test ERROR on soc/for-next ljones-mfd/for-mfd-next linus/master v5.8-rc2 next-20200625]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/0day-ci/linux/commits/Bhanu-Prakash-Maiya/cros-platform-chrome-Add-cros-ec-uart-driver-for-uart-support/20200626-053602
base: https://git.kernel.org/pub/scm/linux/kernel/git/chrome-platform/linux.git for-next
config: i386-allyesconfig (attached as .config)
compiler: gcc-9 (Debian 9.3.0-13) 9.3.0
reproduce (this is a W=1 build):
# save the attached .config to linux build tree
make W=1 ARCH=i386
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
All errors (new ones prefixed by >>):
drivers/platform/chrome/cros_ec_uart.c: In function 'cros_ec_uart_probe':
>> drivers/platform/chrome/cros_ec_uart.c:353:9: error: implicit declaration of function 'cros_ec_register'; did you mean 'driver_register'? [-Werror=implicit-function-declaration]
353 | return cros_ec_register(ec_dev);
| ^~~~~~~~~~~~~~~~
| driver_register
drivers/platform/chrome/cros_ec_uart.c: In function 'cros_ec_uart_remove':
>> drivers/platform/chrome/cros_ec_uart.c:360:2: error: implicit declaration of function 'cros_ec_unregister'; did you mean 'driver_unregister'? [-Werror=implicit-function-declaration]
360 | cros_ec_unregister(ec_dev);
| ^~~~~~~~~~~~~~~~~~
| driver_unregister
drivers/platform/chrome/cros_ec_uart.c: In function 'cros_ec_uart_suspend':
>> drivers/platform/chrome/cros_ec_uart.c:367:9: error: implicit declaration of function 'cros_ec_suspend'; did you mean 'cros_ec_uart_suspend'? [-Werror=implicit-function-declaration]
367 | return cros_ec_suspend(ec_dev);
| ^~~~~~~~~~~~~~~
| cros_ec_uart_suspend
drivers/platform/chrome/cros_ec_uart.c: In function 'cros_ec_uart_resume':
>> drivers/platform/chrome/cros_ec_uart.c:374:9: error: implicit declaration of function 'cros_ec_resume'; did you mean 'cros_ec_uart_resume'? [-Werror=implicit-function-declaration]
374 | return cros_ec_resume(ec_dev);
| ^~~~~~~~~~~~~~
| cros_ec_uart_resume
cc1: some warnings being treated as errors
vim +353 drivers/platform/chrome/cros_ec_uart.c
292
293 static int cros_ec_uart_probe(struct serdev_device *serdev)
294 {
295 struct device *dev = &serdev->dev;
296 struct cros_ec_device *ec_dev;
297 struct cros_ec_uart *ec_uart;
298 int ret;
299
300 ec_uart = devm_kzalloc(dev, sizeof(*ec_uart), GFP_KERNEL);
301 if (!ec_uart)
302 return -ENOMEM;
303
304 ec_dev = devm_kzalloc(dev, sizeof(*ec_dev), GFP_KERNEL);
305 if (!ec_dev)
306 return -ENOMEM;
307
308 ec_uart->serdev = serdev;
309
310 /* Open the serial device */
311 ret = devm_serdev_device_open(dev, ec_uart->serdev);
312 if (ret) {
313 dev_err(dev, "Unable to open UART device %s",
314 dev_name(&serdev->dev));
315 return ret;
316 }
317
318 serdev_device_set_drvdata(serdev, ec_dev);
319
320 serdev_device_set_client_ops(serdev, &cros_ec_uart_client_ops);
321
322 /* Initialize wait queue */
323 init_waitqueue_head(&ec_uart->response.wait_queue);
324
325 ret = cros_ec_uart_acpi_probe(ec_uart);
326 if (ret < 0) {
327 dev_err(dev, "Failed to get ACPI info (%d)", ret);
328 return ret;
329 }
330
331 /* Set baud rate of serial device */
332 ret = serdev_device_set_baudrate(serdev, ec_uart->baudrate);
333 if (ret < 0) {
334 dev_err(dev, "Failed to set up host baud rate (%d)", ret);
335 return ret;
336 }
337
338 /* Set flow control of serial device */
339 serdev_device_set_flow_control(serdev, ec_uart->flowcontrol);
340
341 /* Initialize ec_dev for cros_ec */
342 ec_dev->phys_name = dev_name(&ec_uart->serdev->dev);
343 ec_dev->dev = dev;
344 ec_dev->priv = ec_uart;
345 ec_dev->irq = ec_uart->irq;
346 ec_dev->cmd_xfer = NULL;
347 ec_dev->pkt_xfer = cros_ec_uart_pkt_xfer;
348 ec_dev->din_size = sizeof(struct ec_host_response) +
349 sizeof(struct ec_response_get_protocol_info);
350 ec_dev->dout_size = sizeof(struct ec_host_request);
351
352 /* Register a new cros_ec device */
> 353 return cros_ec_register(ec_dev);
354 }
355
356 static void cros_ec_uart_remove(struct serdev_device *serdev)
357 {
358 struct cros_ec_device *ec_dev = serdev_device_get_drvdata(serdev);
359
> 360 cros_ec_unregister(ec_dev);
361 };
362
363 static int __maybe_unused cros_ec_uart_suspend(struct device *dev)
364 {
365 struct cros_ec_device *ec_dev = dev_get_drvdata(dev);
366
> 367 return cros_ec_suspend(ec_dev);
368 }
369
370 static int __maybe_unused cros_ec_uart_resume(struct device *dev)
371 {
372 struct cros_ec_device *ec_dev = dev_get_drvdata(dev);
373
> 374 return cros_ec_resume(ec_dev);
375 }
376
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 74078 bytes --]
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH 1/2] cros: platform/chrome: Add cros-ec-uart driver for uart support
2020-06-25 21:34 [PATCH 1/2] cros: platform/chrome: Add cros-ec-uart driver for uart support Bhanu Prakash Maiya
2020-06-25 21:34 ` [PATCH 2/2] dt-bindings: mfd: Add DT compatible string "google,cros_ec_uart" Bhanu Prakash Maiya
2020-06-26 0:18 ` [PATCH 1/2] cros: platform/chrome: Add cros-ec-uart driver for uart support kernel test robot
@ 2020-06-26 8:33 ` kernel test robot
2 siblings, 0 replies; 8+ messages in thread
From: kernel test robot @ 2020-06-26 8:33 UTC (permalink / raw)
To: Bhanu Prakash Maiya, linux-arm-kernel
Cc: kbuild-all, clang-built-linux, Benson Leung,
Enric Balletbo i Serra, Guenter Roeck, linux-kernel, Lee Jones ),
Rob Herring, Raul E Rangel, Furquan Shaikh, Duncan Laurie
[-- Attachment #1: Type: text/plain, Size: 5446 bytes --]
Hi Bhanu,
I love your patch! Yet something to improve:
[auto build test ERROR on chrome-platform-linux/for-next]
[also build test ERROR on soc/for-next ljones-mfd/for-mfd-next linus/master v5.8-rc2 next-20200625]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/0day-ci/linux/commits/Bhanu-Prakash-Maiya/cros-platform-chrome-Add-cros-ec-uart-driver-for-uart-support/20200626-053602
base: https://git.kernel.org/pub/scm/linux/kernel/git/chrome-platform/linux.git for-next
config: x86_64-allyesconfig (attached as .config)
compiler: clang version 11.0.0 (https://github.com/llvm/llvm-project 8911a35180c6777188fefe0954a2451a2b91deaf)
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# install x86_64 cross compiling tool for clang build
# apt-get install binutils-x86-64-linux-gnu
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
All errors (new ones prefixed by >>):
>> drivers/platform/chrome/cros_ec_uart.c:353:9: error: implicit declaration of function 'cros_ec_register' [-Werror,-Wimplicit-function-declaration]
return cros_ec_register(ec_dev);
^
>> drivers/platform/chrome/cros_ec_uart.c:360:2: error: implicit declaration of function 'cros_ec_unregister' [-Werror,-Wimplicit-function-declaration]
cros_ec_unregister(ec_dev);
^
>> drivers/platform/chrome/cros_ec_uart.c:367:9: error: implicit declaration of function 'cros_ec_suspend' [-Werror,-Wimplicit-function-declaration]
return cros_ec_suspend(ec_dev);
^
drivers/platform/chrome/cros_ec_uart.c:367:9: note: did you mean 'cros_ec_uart_suspend'?
drivers/platform/chrome/cros_ec_uart.c:363:27: note: 'cros_ec_uart_suspend' declared here
static int __maybe_unused cros_ec_uart_suspend(struct device *dev)
^
>> drivers/platform/chrome/cros_ec_uart.c:374:9: error: implicit declaration of function 'cros_ec_resume' [-Werror,-Wimplicit-function-declaration]
return cros_ec_resume(ec_dev);
^
4 errors generated.
vim +/cros_ec_register +353 drivers/platform/chrome/cros_ec_uart.c
292
293 static int cros_ec_uart_probe(struct serdev_device *serdev)
294 {
295 struct device *dev = &serdev->dev;
296 struct cros_ec_device *ec_dev;
297 struct cros_ec_uart *ec_uart;
298 int ret;
299
300 ec_uart = devm_kzalloc(dev, sizeof(*ec_uart), GFP_KERNEL);
301 if (!ec_uart)
302 return -ENOMEM;
303
304 ec_dev = devm_kzalloc(dev, sizeof(*ec_dev), GFP_KERNEL);
305 if (!ec_dev)
306 return -ENOMEM;
307
308 ec_uart->serdev = serdev;
309
310 /* Open the serial device */
311 ret = devm_serdev_device_open(dev, ec_uart->serdev);
312 if (ret) {
313 dev_err(dev, "Unable to open UART device %s",
314 dev_name(&serdev->dev));
315 return ret;
316 }
317
318 serdev_device_set_drvdata(serdev, ec_dev);
319
320 serdev_device_set_client_ops(serdev, &cros_ec_uart_client_ops);
321
322 /* Initialize wait queue */
323 init_waitqueue_head(&ec_uart->response.wait_queue);
324
325 ret = cros_ec_uart_acpi_probe(ec_uart);
326 if (ret < 0) {
327 dev_err(dev, "Failed to get ACPI info (%d)", ret);
328 return ret;
329 }
330
331 /* Set baud rate of serial device */
332 ret = serdev_device_set_baudrate(serdev, ec_uart->baudrate);
333 if (ret < 0) {
334 dev_err(dev, "Failed to set up host baud rate (%d)", ret);
335 return ret;
336 }
337
338 /* Set flow control of serial device */
339 serdev_device_set_flow_control(serdev, ec_uart->flowcontrol);
340
341 /* Initialize ec_dev for cros_ec */
342 ec_dev->phys_name = dev_name(&ec_uart->serdev->dev);
343 ec_dev->dev = dev;
344 ec_dev->priv = ec_uart;
345 ec_dev->irq = ec_uart->irq;
346 ec_dev->cmd_xfer = NULL;
347 ec_dev->pkt_xfer = cros_ec_uart_pkt_xfer;
348 ec_dev->din_size = sizeof(struct ec_host_response) +
349 sizeof(struct ec_response_get_protocol_info);
350 ec_dev->dout_size = sizeof(struct ec_host_request);
351
352 /* Register a new cros_ec device */
> 353 return cros_ec_register(ec_dev);
354 }
355
356 static void cros_ec_uart_remove(struct serdev_device *serdev)
357 {
358 struct cros_ec_device *ec_dev = serdev_device_get_drvdata(serdev);
359
> 360 cros_ec_unregister(ec_dev);
361 };
362
363 static int __maybe_unused cros_ec_uart_suspend(struct device *dev)
364 {
365 struct cros_ec_device *ec_dev = dev_get_drvdata(dev);
366
> 367 return cros_ec_suspend(ec_dev);
368 }
369
370 static int __maybe_unused cros_ec_uart_resume(struct device *dev)
371 {
372 struct cros_ec_device *ec_dev = dev_get_drvdata(dev);
373
> 374 return cros_ec_resume(ec_dev);
375 }
376
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 75301 bytes --]
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH 2/2] dt-bindings: mfd: Add DT compatible string "google,cros_ec_uart"
2020-06-25 21:34 ` [PATCH 2/2] dt-bindings: mfd: Add DT compatible string "google,cros_ec_uart" Bhanu Prakash Maiya
@ 2020-06-26 8:42 ` Enric Balletbo i Serra
0 siblings, 0 replies; 8+ messages in thread
From: Enric Balletbo i Serra @ 2020-06-26 8:42 UTC (permalink / raw)
To: Bhanu Prakash Maiya, linux-arm-kernel
Cc: Benson Leung, Guenter Roeck, linux-kernel, Lee Jones ),
Rob Herring, Raul E Rangel, Furquan Shaikh, Duncan Laurie,
Eric Peers, devicetree, Bhanu Prakash Maiya
Hi Bhanu,
Thank you for the patch.
On 25/6/20 23:34, Bhanu Prakash Maiya wrote:
> Add DT compatible string in
> Documentation/devicetree/bindings/mfd/cros_ec.txt
>
> Signed-off-by: Bhanu Prakash Maiya <bhanumaiya@google.com>
> ---
>
> Documentation/devicetree/bindings/mfd/cros-ec.txt | 9 +++++++--
txt bindings are somewhat deprecated now, this specific binding was already
converted to the new json-schema, although didn't land yet, you should base your
changes on that, you can pick the following patch:
https://patchwork.ozlabs.org/project/devicetree-bindings/patch/20200306085513.76024-1-ikjn@chromium.org/
Also, the kernel test robot, reported a build problem, so fix the problems on
the second version.
Thanks,
Enric
> 1 file changed, 7 insertions(+), 2 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/mfd/cros-ec.txt b/Documentation/devicetree/bindings/mfd/cros-ec.txt
> index 4860eabd0f729..ec8c5d7ecc266 100644
> --- a/Documentation/devicetree/bindings/mfd/cros-ec.txt
> +++ b/Documentation/devicetree/bindings/mfd/cros-ec.txt
> @@ -3,7 +3,7 @@ ChromeOS Embedded Controller
> Google's ChromeOS EC is a Cortex-M device which talks to the AP and
> implements various function such as keyboard and battery charging.
>
> -The EC can be connect through various means (I2C, SPI, LPC, RPMSG) and the
> +The EC can be connect through various means (I2C, SPI, UART, LPC, RPMSG) and the
> compatible string used depends on the interface. Each connection method has
> its own driver which connects to the top level interface-agnostic EC driver.
> Other Linux driver (such as cros-ec-keyb for the matrix keyboard) connect to
> @@ -17,6 +17,10 @@ Required properties (SPI):
> - compatible: "google,cros-ec-spi"
> - reg: SPI chip select
>
> +Required properties (UART):
> +- compatible: "google,cros-ec-uart"
> +- reg: UART baudrate, flowcontrol
> +
> Required properties (RPMSG):
> - compatible: "google,cros-ec-rpmsg"
>
> @@ -72,5 +76,6 @@ spi@131b0000 {
> };
> };
>
> -
> Example for LPC is not supplied as it is not yet implemented.
> +
> +Example for UART is not supplied as it is not yet implemented.
>
^ permalink raw reply [flat|nested] 8+ messages in thread
* [PATCH 1/2] cros: platform/chrome: Add cros-ec-uart driver for uart support
@ 2020-07-15 8:20 Bhanu Prakash Maiya
0 siblings, 0 replies; 8+ messages in thread
From: Bhanu Prakash Maiya @ 2020-07-15 8:20 UTC (permalink / raw)
To: linux-arm-kernel
Cc: Lee Jones, Furquan Shaikh, Raul E Rangel, Eric Peers,
Duncan Laurie, Benson Leung, Enric Balletbo i Serra,
Bhanu Prakash Maiya, Guenter Roeck, Mauro Carvalho Chehab,
David S . Miller, Rob Herring, Greg Kroah-Hartman, devicetree,
linux-kernel, kernel test robot
From: Bhanu Prakash Maiya <bhanumaiya@chromium.org>
This patch enables uart transport layer for cros_ec framework.
The cros-ec-uart binds with EC device working on uart transport to
send request and receive response.
Signed-off-by: Bhanu Prakash Maiya <bhanumaiya@chromium.org>
Reported-by: kernel test robot <lkp@intel.com>
Change-Id: Icb23b633700f1ef4d123e3f21fd26fad21a3f207
---
Changes in v2:
1: Fixed build error on v1.
2: Changed EC timeout for response packet to 3 Sec and added comments.
3: Fixed cros_ec_uart_rx_bytes function to handle rx buffer < size of response header.
MAINTAINERS | 1 +
drivers/platform/chrome/Kconfig | 10 +
drivers/platform/chrome/Makefile | 1 +
drivers/platform/chrome/cros_ec_uart.c | 411 +++++++++++++++++++++++++
4 files changed, 423 insertions(+)
create mode 100644 drivers/platform/chrome/cros_ec_uart.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 50659d76976b7..aa8e1d121c1d7 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4036,6 +4036,7 @@ F: sound/soc/codecs/cros_ec_codec.*
CHROMEOS EC SUBDRIVERS
M: Benson Leung <bleung@chromium.org>
M: Enric Balletbo i Serra <enric.balletbo@collabora.com>
+M: Bhanu Prakash Maiya <bhanumaiya@chromium.org>
R: Guenter Roeck <groeck@chromium.org>
S: Maintained
F: drivers/power/supply/cros_usbpd-charger.c
diff --git a/drivers/platform/chrome/Kconfig b/drivers/platform/chrome/Kconfig
index 3822e5e111caa..2082fafe08a6a 100644
--- a/drivers/platform/chrome/Kconfig
+++ b/drivers/platform/chrome/Kconfig
@@ -125,6 +125,16 @@ config CROS_EC_SPI
response time cannot be guaranteed, we support ignoring
'pre-amble' bytes before the response actually starts.
+config CROS_EC_UART
+ tristate "ChromeOS Embedded Controller (UART)"
+ depends on CROS_EC && ACPI && SERIAL_DEV_BUS
+ help
+ If you say Y here, you get support for talking to the ChromeOS EC
+ through a UART, using a byte-level protocol.
+
+ To compile this driver as a module, choose M here: the
+ module will be called cros_ec_uart.
+
config CROS_EC_LPC
tristate "ChromeOS Embedded Controller (LPC)"
depends on CROS_EC && ACPI && (X86 || COMPILE_TEST)
diff --git a/drivers/platform/chrome/Makefile b/drivers/platform/chrome/Makefile
index 8ed1e33033b38..fc449351fc794 100644
--- a/drivers/platform/chrome/Makefile
+++ b/drivers/platform/chrome/Makefile
@@ -12,6 +12,7 @@ obj-$(CONFIG_CROS_EC_I2C) += cros_ec_i2c.o
obj-$(CONFIG_CROS_EC_ISHTP) += cros_ec_ishtp.o
obj-$(CONFIG_CROS_EC_RPMSG) += cros_ec_rpmsg.o
obj-$(CONFIG_CROS_EC_SPI) += cros_ec_spi.o
+obj-$(CONFIG_CROS_EC_UART) += cros_ec_uart.o
cros_ec_lpcs-objs := cros_ec_lpc.o cros_ec_lpc_mec.o
obj-$(CONFIG_CROS_EC_TYPEC) += cros_ec_typec.o
obj-$(CONFIG_CROS_EC_LPC) += cros_ec_lpcs.o
diff --git a/drivers/platform/chrome/cros_ec_uart.c b/drivers/platform/chrome/cros_ec_uart.c
new file mode 100644
index 0000000000000..9a0ba884b6812
--- /dev/null
+++ b/drivers/platform/chrome/cros_ec_uart.c
@@ -0,0 +1,411 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * UART interface for ChromeOS Embedded Controller
+ *
+ * Copyright 2020 Google LLC.
+ */
+
+#include <linux/delay.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/acpi.h>
+#include <linux/of.h>
+#include <linux/platform_data/cros_ec_commands.h>
+#include <linux/platform_data/cros_ec_proto.h>
+#include <linux/serdev.h>
+#include <linux/slab.h>
+#include <uapi/linux/sched/types.h>
+
+#include "cros_ec.h"
+
+/*
+ * EC sends contiguous bytes of response packet on UART AP RX.
+ * TTY driver in AP accumulates incoming bytes and calls the registered callback
+ * function. Byte count can range from 1 to Max count supported by TTY driver.
+ * This driver should wait for long time for all callbacks to be processed.
+ * Considering the worst case scenario, wait for ~3 secs. This timeout should
+ * account for max latency and some additional guard time.
+ * In case the packet is received in ms, wait queue will be released and packet
+ * will be processed.
+ */
+#define EC_MSG_DEADLINE_MS (300 * 10)
+
+/**
+ * struct response_info - Encapsulate EC response related
+ * information for passing between function
+ * cros_ec_uart_pkt_xfer() and cros_ec_uart_rx_bytes()
+ * callback.
+ * @data: Copy the data received from EC here.
+ * @max_size: Max size allocated for the @data buffer. If the
+ * received data exceeds this value, we log an error.
+ * @size: Actual size of data received from EC. This is also
+ * used to accumulate byte count with response is received
+ * in dma chunks.
+ * @exp_len: Expected bytes of response from EC including header.
+ * @error: 0 for success, negative error code for a failure.
+ * @received: Set to true on receiving a valid EC response.
+ * @wait_queue: Wait queue EC response where the cros_ec sends request
+ * to EC and waits
+ */
+struct response_info {
+ void *data;
+ size_t max_size;
+ size_t size;
+ int error;
+ size_t exp_len;
+ bool received;
+ wait_queue_head_t wait_queue;
+};
+
+/**
+ * struct cros_ec_uart - information about a uart-connected EC
+ *
+ * @serdev_device: serdev uart device we are connected to.
+ * @baudrate: UART baudrate of attached EC device.
+ * @flowcontrol: UART flowcontrol of attached device.
+ * @irq: Linux IRQ number of associated serial device.
+ * @response: Response info passing between cros_ec_uart_pkt_xfer()
+ * and cros_ec_uart_rx_bytes()
+ */
+struct cros_ec_uart {
+ struct serdev_device *serdev;
+ u32 baudrate;
+ u8 flowcontrol;
+ u32 irq;
+ struct response_info response;
+};
+
+static int cros_ec_uart_rx_bytes(struct serdev_device *serdev,
+ const u8 *data,
+ size_t count)
+{
+ struct ec_host_response *response;
+ struct cros_ec_device *ec_dev = serdev_device_get_drvdata(serdev);
+ struct cros_ec_uart *ec_uart = ec_dev->priv;
+
+ /* Check if bytes were sent out of band */
+ if (!ec_uart->response.data) {
+ /* Discard all bytes */
+ return count;
+ }
+
+ /*
+ * Check if incoming bytes + response.size are less than allocated
+ * buffer in din by cros_ec. This will ensure that if EC sends more
+ * bytes than max_size, waiting process will be notified with an error.
+ */
+ if (ec_uart->response.size + count <= ec_uart->response.max_size) {
+ /* Copy bytes in data in buffer */
+ memcpy((void *)ec_uart->response.data + ec_uart->response.size,
+ (void *)data, count);
+
+ /* Add incoming bytes in size */
+ ec_uart->response.size += count;
+
+ /*
+ * Read data_len if we received response header and if exp_len
+ * was not read before.
+ */
+ if (ec_uart->response.size >= sizeof(*response) &&
+ ec_uart->response.exp_len == 0) {
+ /* Get expected response length from response header */
+ response = (struct ec_host_response *)
+ ec_uart->response.data;
+
+ ec_uart->response.exp_len = response->data_len +
+ sizeof(*response);
+ }
+
+ /*
+ * If driver received response header and payload from EC,
+ * Wake up the wait queue.
+ */
+ if (ec_uart->response.size >= sizeof(*response) &&
+ ec_uart->response.size == ec_uart->response.exp_len) {
+ /* Set flag before waking up the caller */
+ ec_uart->response.received = true;
+
+ /* Wake the calling thread */
+ wake_up_interruptible(&ec_uart->response.wait_queue);
+ }
+ } else {
+ /* Received bytes are more the allocated buffer*/
+ ec_uart->response.error = -EMSGSIZE;
+
+ /* Wake the calling thread */
+ wake_up_interruptible(&ec_uart->response.wait_queue);
+ }
+
+ return count;
+}
+
+static int cros_ec_uart_pkt_xfer(struct cros_ec_device *ec_dev,
+ struct cros_ec_command *ec_msg)
+{
+ struct cros_ec_uart *ec_uart = ec_dev->priv;
+ struct serdev_device *serdev = ec_uart->serdev;
+ struct ec_host_response *response;
+ unsigned int len;
+ int ret, i;
+ u8 sum = 0;
+
+ /* Prepare an outgoing message in the output buffer */
+ len = cros_ec_prepare_tx(ec_dev, ec_msg);
+ dev_dbg(ec_dev->dev, "Prepared len=%d\n", len);
+
+ /* Setup for incoming response */
+ ec_uart->response.data = ec_dev->din;
+ ec_uart->response.max_size = ec_dev->din_size;
+ ec_uart->response.size = 0;
+ ec_uart->response.error = 0;
+ ec_uart->response.exp_len = 0;
+ ec_uart->response.received = false;
+
+ /* Write serial device buffer */
+ ret = serdev_device_write_buf(serdev, ec_dev->dout, len);
+ if (ret < len) {
+ dev_err(&serdev->dev,
+ "Unable to write data to serial device %s",
+ dev_name(&serdev->dev));
+
+ /* Return EIO as controller had issues writing buffer */
+ ret = -EIO;
+ goto exit;
+ }
+
+ /* Once request is successfully sent to EC, wait to wait_queue */
+ wait_event_interruptible_timeout(ec_uart->response.wait_queue,
+ ec_uart->response.received,
+ msecs_to_jiffies(EC_MSG_DEADLINE_MS));
+
+ /* Check if wait_queue was interrupted due to an error */
+ if (ec_uart->response.error < 0) {
+ dev_warn(&serdev->dev, "Response error detected.\n");
+
+ ret = ec_uart->response.error;
+ goto exit;
+ }
+
+ /* Check if valid response was received or there was a timeout */
+ if (!ec_uart->response.received) {
+ dev_warn(&serdev->dev, "EC failed to respond in time.\n");
+
+ ret = -ETIMEDOUT;
+ goto exit;
+ }
+
+ /* Check response error code */
+ response = (struct ec_host_response *)ec_dev->din;
+ ec_msg->result = response->result;
+
+ /* Check if received response is longer than expected */
+ if (response->data_len > ec_msg->insize) {
+ dev_err(ec_dev->dev, "Resp too long (%d bytes, expected %d)",
+ response->data_len,
+ ec_msg->insize);
+ ret = -ENOSPC;
+ goto exit;
+ }
+
+ /* Copy response packet to ec_msg data buffer */
+ memcpy(ec_msg->data,
+ ec_dev->din + sizeof(*response),
+ response->data_len);
+
+ /* Add all response header bytes for checksum calculation */
+ for (i = 0; i < sizeof(*response); i++)
+ sum += ec_dev->din[i];
+
+ /* Copy response packet payload and compute checksum */
+ for (i = 0; i < response->data_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;
+ }
+
+ /* Return data_len to cros_ec */
+ ret = response->data_len;
+
+exit:
+ /* Reset ec_uart */
+ ec_uart->response.data = NULL;
+ ec_uart->response.max_size = 0;
+ ec_uart->response.size = 0;
+ ec_uart->response.error = 0;
+ ec_uart->response.exp_len = 0;
+ ec_uart->response.received = false;
+
+ if (ec_msg->command == EC_CMD_REBOOT_EC)
+ msleep(EC_REBOOT_DELAY_MS);
+
+ return ret;
+}
+
+static int cros_ec_uart_resource(struct acpi_resource *ares, void *data)
+{
+ struct cros_ec_uart *ec_uart = data;
+ struct acpi_resource_uart_serialbus *sb;
+
+ switch (ares->type) {
+ case ACPI_RESOURCE_TYPE_SERIAL_BUS:
+ sb = &ares->data.uart_serial_bus;
+ if (sb->type == ACPI_RESOURCE_SERIAL_TYPE_UART) {
+ ec_uart->baudrate = sb->default_baud_rate;
+ dev_dbg(&ec_uart->serdev->dev, "Baudrate %d\n",
+ ec_uart->baudrate);
+
+ ec_uart->flowcontrol = sb->flow_control;
+ dev_dbg(&ec_uart->serdev->dev, "Flow control %d\n",
+ ec_uart->flowcontrol);
+ }
+ break;
+ default:
+ break;
+ }
+
+ return 0;
+}
+
+static int cros_ec_uart_acpi_probe(struct cros_ec_uart *ec_uart)
+{
+ LIST_HEAD(resources);
+ struct acpi_device *adev = ACPI_COMPANION(&ec_uart->serdev->dev);
+ int ret;
+
+ /* Retrieve UART ACPI info */
+ ret = acpi_dev_get_resources(adev, &resources,
+ cros_ec_uart_resource, ec_uart);
+ if (ret < 0)
+ return ret;
+
+ acpi_dev_free_resource_list(&resources);
+
+ /* Retrieve GpioInt and translate it to Linux IRQ number */
+ ret = acpi_dev_gpio_irq_get(adev, 0);
+ if (ret < 0)
+ return ret;
+
+ ec_uart->irq = ret;
+ dev_dbg(&ec_uart->serdev->dev, "IRQ number %d\n", ec_uart->irq);
+
+ return 0;
+}
+
+static const struct serdev_device_ops cros_ec_uart_client_ops = {
+ .receive_buf = cros_ec_uart_rx_bytes,
+};
+
+static int cros_ec_uart_probe(struct serdev_device *serdev)
+{
+ struct device *dev = &serdev->dev;
+ struct cros_ec_device *ec_dev;
+ struct cros_ec_uart *ec_uart;
+ int ret;
+
+ ec_uart = devm_kzalloc(dev, sizeof(*ec_uart), GFP_KERNEL);
+ if (!ec_uart)
+ return -ENOMEM;
+
+ ec_dev = devm_kzalloc(dev, sizeof(*ec_dev), GFP_KERNEL);
+ if (!ec_dev)
+ return -ENOMEM;
+
+ ec_uart->serdev = serdev;
+
+ /* Open the serial device */
+ ret = devm_serdev_device_open(dev, ec_uart->serdev);
+ if (ret) {
+ dev_err(dev, "Unable to open UART device %s",
+ dev_name(&serdev->dev));
+ return ret;
+ }
+
+ serdev_device_set_drvdata(serdev, ec_dev);
+
+ serdev_device_set_client_ops(serdev, &cros_ec_uart_client_ops);
+
+ /* Initialize wait queue */
+ init_waitqueue_head(&ec_uart->response.wait_queue);
+
+ ret = cros_ec_uart_acpi_probe(ec_uart);
+ if (ret < 0) {
+ dev_err(dev, "Failed to get ACPI info (%d)", ret);
+ return ret;
+ }
+
+ /* Set baud rate of serial device */
+ ret = serdev_device_set_baudrate(serdev, ec_uart->baudrate);
+ if (ret < 0) {
+ dev_err(dev, "Failed to set up host baud rate (%d)", ret);
+ return ret;
+ }
+
+ /* Set flow control of serial device */
+ serdev_device_set_flow_control(serdev, ec_uart->flowcontrol);
+
+ /* Initialize ec_dev for cros_ec */
+ ec_dev->phys_name = dev_name(&ec_uart->serdev->dev);
+ ec_dev->dev = dev;
+ ec_dev->priv = ec_uart;
+ ec_dev->irq = ec_uart->irq;
+ ec_dev->cmd_xfer = NULL;
+ ec_dev->pkt_xfer = cros_ec_uart_pkt_xfer;
+ ec_dev->din_size = sizeof(struct ec_host_response) +
+ sizeof(struct ec_response_get_protocol_info);
+ ec_dev->dout_size = sizeof(struct ec_host_request);
+
+ /* Register a new cros_ec device */
+ return cros_ec_register(ec_dev);
+}
+
+static void cros_ec_uart_remove(struct serdev_device *serdev)
+{
+ struct cros_ec_device *ec_dev = serdev_device_get_drvdata(serdev);
+
+ cros_ec_unregister(ec_dev);
+};
+
+static int __maybe_unused cros_ec_uart_suspend(struct device *dev)
+{
+ struct cros_ec_device *ec_dev = dev_get_drvdata(dev);
+
+ return cros_ec_suspend(ec_dev);
+}
+
+static int __maybe_unused cros_ec_uart_resume(struct device *dev)
+{
+ struct cros_ec_device *ec_dev = dev_get_drvdata(dev);
+
+ return cros_ec_resume(ec_dev);
+}
+
+static SIMPLE_DEV_PM_OPS(cros_ec_uart_pm_ops, cros_ec_uart_suspend,
+ cros_ec_uart_resume);
+
+static const struct of_device_id cros_ec_uart_of_match[] = {
+ { .compatible = "google,cros-ec-uart" },
+ {}
+};
+
+static struct serdev_device_driver cros_ec_uart_driver = {
+ .driver = {
+ .name = "cros-ec-uart",
+ .of_match_table = cros_ec_uart_of_match,
+ .pm = &cros_ec_uart_pm_ops,
+ },
+ .probe = cros_ec_uart_probe,
+ .remove = cros_ec_uart_remove,
+};
+
+module_serdev_device_driver(cros_ec_uart_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("UART interface for ChromeOS Embedded Controller");
+MODULE_AUTHOR("Bhanu Prakash Maiya <bhanumaiya@chromium.org>");
--
2.26.2
^ permalink raw reply related [flat|nested] 8+ messages in thread
* Re: [PATCH 1/2] cros: platform/chrome: Add cros-ec-uart driver for uart support
2020-07-15 7:41 Bhanu Prakash Maiya
@ 2020-07-15 7:56 ` Greg Kroah-Hartman
0 siblings, 0 replies; 8+ messages in thread
From: Greg Kroah-Hartman @ 2020-07-15 7:56 UTC (permalink / raw)
To: Bhanu Prakash Maiya
Cc: linux-arm-kernel, Lee Jones, Furquan Shaikh, Raul E Rangel,
Eric Peers, Duncan Laurie, Benson Leung, Enric Balletbo i Serra,
Guenter Roeck, Mauro Carvalho Chehab, David S . Miller,
Rob Herring, devicetree, linux-kernel, kernel test robot
On Wed, Jul 15, 2020 at 12:41:06AM -0700, Bhanu Prakash Maiya wrote:
> From: Bhanu Prakash Maiya <bhanumaiya@chromium.org>
>
> This patch enables uart transport layer for cros_ec framework.
> The cros-ec-uart binds with EC device working on uart transport to
> send request and receive response.
>
> Signed-off-by: Bhanu Prakash Maiya <bhanumaiya@chromium.org>
> Reported-by: kernel test robot <lkp@intel.com>
> Change-Id: Icb23b633700f1ef4d123e3f21fd26fad21a3f207
I think you forgot to run checkpatch.pl on this :(
^ permalink raw reply [flat|nested] 8+ messages in thread
* [PATCH 1/2] cros: platform/chrome: Add cros-ec-uart driver for uart support
@ 2020-07-15 7:41 Bhanu Prakash Maiya
2020-07-15 7:56 ` Greg Kroah-Hartman
0 siblings, 1 reply; 8+ messages in thread
From: Bhanu Prakash Maiya @ 2020-07-15 7:41 UTC (permalink / raw)
To: linux-arm-kernel
Cc: Lee Jones, Furquan Shaikh, Raul E Rangel, Eric Peers,
Duncan Laurie, Benson Leung, Enric Balletbo i Serra,
Bhanu Prakash Maiya, Guenter Roeck, Mauro Carvalho Chehab,
David S . Miller, Rob Herring, Greg Kroah-Hartman, devicetree,
linux-kernel, kernel test robot
From: Bhanu Prakash Maiya <bhanumaiya@chromium.org>
This patch enables uart transport layer for cros_ec framework.
The cros-ec-uart binds with EC device working on uart transport to
send request and receive response.
Signed-off-by: Bhanu Prakash Maiya <bhanumaiya@chromium.org>
Reported-by: kernel test robot <lkp@intel.com>
Change-Id: Icb23b633700f1ef4d123e3f21fd26fad21a3f207
---
MAINTAINERS | 1 +
drivers/platform/chrome/Kconfig | 10 +
drivers/platform/chrome/Makefile | 1 +
drivers/platform/chrome/cros_ec_uart.c | 411 +++++++++++++++++++++++++
4 files changed, 423 insertions(+)
create mode 100644 drivers/platform/chrome/cros_ec_uart.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 50659d76976b7..aa8e1d121c1d7 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4036,6 +4036,7 @@ F: sound/soc/codecs/cros_ec_codec.*
CHROMEOS EC SUBDRIVERS
M: Benson Leung <bleung@chromium.org>
M: Enric Balletbo i Serra <enric.balletbo@collabora.com>
+M: Bhanu Prakash Maiya <bhanumaiya@chromium.org>
R: Guenter Roeck <groeck@chromium.org>
S: Maintained
F: drivers/power/supply/cros_usbpd-charger.c
diff --git a/drivers/platform/chrome/Kconfig b/drivers/platform/chrome/Kconfig
index 3822e5e111caa..2082fafe08a6a 100644
--- a/drivers/platform/chrome/Kconfig
+++ b/drivers/platform/chrome/Kconfig
@@ -125,6 +125,16 @@ config CROS_EC_SPI
response time cannot be guaranteed, we support ignoring
'pre-amble' bytes before the response actually starts.
+config CROS_EC_UART
+ tristate "ChromeOS Embedded Controller (UART)"
+ depends on CROS_EC && ACPI && SERIAL_DEV_BUS
+ help
+ If you say Y here, you get support for talking to the ChromeOS EC
+ through a UART, using a byte-level protocol.
+
+ To compile this driver as a module, choose M here: the
+ module will be called cros_ec_uart.
+
config CROS_EC_LPC
tristate "ChromeOS Embedded Controller (LPC)"
depends on CROS_EC && ACPI && (X86 || COMPILE_TEST)
diff --git a/drivers/platform/chrome/Makefile b/drivers/platform/chrome/Makefile
index 8ed1e33033b38..fc449351fc794 100644
--- a/drivers/platform/chrome/Makefile
+++ b/drivers/platform/chrome/Makefile
@@ -12,6 +12,7 @@ obj-$(CONFIG_CROS_EC_I2C) += cros_ec_i2c.o
obj-$(CONFIG_CROS_EC_ISHTP) += cros_ec_ishtp.o
obj-$(CONFIG_CROS_EC_RPMSG) += cros_ec_rpmsg.o
obj-$(CONFIG_CROS_EC_SPI) += cros_ec_spi.o
+obj-$(CONFIG_CROS_EC_UART) += cros_ec_uart.o
cros_ec_lpcs-objs := cros_ec_lpc.o cros_ec_lpc_mec.o
obj-$(CONFIG_CROS_EC_TYPEC) += cros_ec_typec.o
obj-$(CONFIG_CROS_EC_LPC) += cros_ec_lpcs.o
diff --git a/drivers/platform/chrome/cros_ec_uart.c b/drivers/platform/chrome/cros_ec_uart.c
new file mode 100644
index 0000000000000..9a0ba884b6812
--- /dev/null
+++ b/drivers/platform/chrome/cros_ec_uart.c
@@ -0,0 +1,411 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * UART interface for ChromeOS Embedded Controller
+ *
+ * Copyright 2020 Google LLC.
+ */
+
+#include <linux/delay.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/acpi.h>
+#include <linux/of.h>
+#include <linux/platform_data/cros_ec_commands.h>
+#include <linux/platform_data/cros_ec_proto.h>
+#include <linux/serdev.h>
+#include <linux/slab.h>
+#include <uapi/linux/sched/types.h>
+
+#include "cros_ec.h"
+
+/*
+ * EC sends contiguous bytes of response packet on UART AP RX.
+ * TTY driver in AP accumulates incoming bytes and calls the registered callback
+ * function. Byte count can range from 1 to Max count supported by TTY driver.
+ * This driver should wait for long time for all callbacks to be processed.
+ * Considering the worst case scenario, wait for ~3 secs. This timeout should
+ * account for max latency and some additional guard time.
+ * In case the packet is received in ms, wait queue will be released and packet
+ * will be processed.
+ */
+#define EC_MSG_DEADLINE_MS (300 * 10)
+
+/**
+ * struct response_info - Encapsulate EC response related
+ * information for passing between function
+ * cros_ec_uart_pkt_xfer() and cros_ec_uart_rx_bytes()
+ * callback.
+ * @data: Copy the data received from EC here.
+ * @max_size: Max size allocated for the @data buffer. If the
+ * received data exceeds this value, we log an error.
+ * @size: Actual size of data received from EC. This is also
+ * used to accumulate byte count with response is received
+ * in dma chunks.
+ * @exp_len: Expected bytes of response from EC including header.
+ * @error: 0 for success, negative error code for a failure.
+ * @received: Set to true on receiving a valid EC response.
+ * @wait_queue: Wait queue EC response where the cros_ec sends request
+ * to EC and waits
+ */
+struct response_info {
+ void *data;
+ size_t max_size;
+ size_t size;
+ int error;
+ size_t exp_len;
+ bool received;
+ wait_queue_head_t wait_queue;
+};
+
+/**
+ * struct cros_ec_uart - information about a uart-connected EC
+ *
+ * @serdev_device: serdev uart device we are connected to.
+ * @baudrate: UART baudrate of attached EC device.
+ * @flowcontrol: UART flowcontrol of attached device.
+ * @irq: Linux IRQ number of associated serial device.
+ * @response: Response info passing between cros_ec_uart_pkt_xfer()
+ * and cros_ec_uart_rx_bytes()
+ */
+struct cros_ec_uart {
+ struct serdev_device *serdev;
+ u32 baudrate;
+ u8 flowcontrol;
+ u32 irq;
+ struct response_info response;
+};
+
+static int cros_ec_uart_rx_bytes(struct serdev_device *serdev,
+ const u8 *data,
+ size_t count)
+{
+ struct ec_host_response *response;
+ struct cros_ec_device *ec_dev = serdev_device_get_drvdata(serdev);
+ struct cros_ec_uart *ec_uart = ec_dev->priv;
+
+ /* Check if bytes were sent out of band */
+ if (!ec_uart->response.data) {
+ /* Discard all bytes */
+ return count;
+ }
+
+ /*
+ * Check if incoming bytes + response.size are less than allocated
+ * buffer in din by cros_ec. This will ensure that if EC sends more
+ * bytes than max_size, waiting process will be notified with an error.
+ */
+ if (ec_uart->response.size + count <= ec_uart->response.max_size) {
+ /* Copy bytes in data in buffer */
+ memcpy((void *)ec_uart->response.data + ec_uart->response.size,
+ (void *)data, count);
+
+ /* Add incoming bytes in size */
+ ec_uart->response.size += count;
+
+ /*
+ * Read data_len if we received response header and if exp_len
+ * was not read before.
+ */
+ if (ec_uart->response.size >= sizeof(*response) &&
+ ec_uart->response.exp_len == 0) {
+ /* Get expected response length from response header */
+ response = (struct ec_host_response *)
+ ec_uart->response.data;
+
+ ec_uart->response.exp_len = response->data_len +
+ sizeof(*response);
+ }
+
+ /*
+ * If driver received response header and payload from EC,
+ * Wake up the wait queue.
+ */
+ if (ec_uart->response.size >= sizeof(*response) &&
+ ec_uart->response.size == ec_uart->response.exp_len) {
+ /* Set flag before waking up the caller */
+ ec_uart->response.received = true;
+
+ /* Wake the calling thread */
+ wake_up_interruptible(&ec_uart->response.wait_queue);
+ }
+ } else {
+ /* Received bytes are more the allocated buffer*/
+ ec_uart->response.error = -EMSGSIZE;
+
+ /* Wake the calling thread */
+ wake_up_interruptible(&ec_uart->response.wait_queue);
+ }
+
+ return count;
+}
+
+static int cros_ec_uart_pkt_xfer(struct cros_ec_device *ec_dev,
+ struct cros_ec_command *ec_msg)
+{
+ struct cros_ec_uart *ec_uart = ec_dev->priv;
+ struct serdev_device *serdev = ec_uart->serdev;
+ struct ec_host_response *response;
+ unsigned int len;
+ int ret, i;
+ u8 sum = 0;
+
+ /* Prepare an outgoing message in the output buffer */
+ len = cros_ec_prepare_tx(ec_dev, ec_msg);
+ dev_dbg(ec_dev->dev, "Prepared len=%d\n", len);
+
+ /* Setup for incoming response */
+ ec_uart->response.data = ec_dev->din;
+ ec_uart->response.max_size = ec_dev->din_size;
+ ec_uart->response.size = 0;
+ ec_uart->response.error = 0;
+ ec_uart->response.exp_len = 0;
+ ec_uart->response.received = false;
+
+ /* Write serial device buffer */
+ ret = serdev_device_write_buf(serdev, ec_dev->dout, len);
+ if (ret < len) {
+ dev_err(&serdev->dev,
+ "Unable to write data to serial device %s",
+ dev_name(&serdev->dev));
+
+ /* Return EIO as controller had issues writing buffer */
+ ret = -EIO;
+ goto exit;
+ }
+
+ /* Once request is successfully sent to EC, wait to wait_queue */
+ wait_event_interruptible_timeout(ec_uart->response.wait_queue,
+ ec_uart->response.received,
+ msecs_to_jiffies(EC_MSG_DEADLINE_MS));
+
+ /* Check if wait_queue was interrupted due to an error */
+ if (ec_uart->response.error < 0) {
+ dev_warn(&serdev->dev, "Response error detected.\n");
+
+ ret = ec_uart->response.error;
+ goto exit;
+ }
+
+ /* Check if valid response was received or there was a timeout */
+ if (!ec_uart->response.received) {
+ dev_warn(&serdev->dev, "EC failed to respond in time.\n");
+
+ ret = -ETIMEDOUT;
+ goto exit;
+ }
+
+ /* Check response error code */
+ response = (struct ec_host_response *)ec_dev->din;
+ ec_msg->result = response->result;
+
+ /* Check if received response is longer than expected */
+ if (response->data_len > ec_msg->insize) {
+ dev_err(ec_dev->dev, "Resp too long (%d bytes, expected %d)",
+ response->data_len,
+ ec_msg->insize);
+ ret = -ENOSPC;
+ goto exit;
+ }
+
+ /* Copy response packet to ec_msg data buffer */
+ memcpy(ec_msg->data,
+ ec_dev->din + sizeof(*response),
+ response->data_len);
+
+ /* Add all response header bytes for checksum calculation */
+ for (i = 0; i < sizeof(*response); i++)
+ sum += ec_dev->din[i];
+
+ /* Copy response packet payload and compute checksum */
+ for (i = 0; i < response->data_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;
+ }
+
+ /* Return data_len to cros_ec */
+ ret = response->data_len;
+
+exit:
+ /* Reset ec_uart */
+ ec_uart->response.data = NULL;
+ ec_uart->response.max_size = 0;
+ ec_uart->response.size = 0;
+ ec_uart->response.error = 0;
+ ec_uart->response.exp_len = 0;
+ ec_uart->response.received = false;
+
+ if (ec_msg->command == EC_CMD_REBOOT_EC)
+ msleep(EC_REBOOT_DELAY_MS);
+
+ return ret;
+}
+
+static int cros_ec_uart_resource(struct acpi_resource *ares, void *data)
+{
+ struct cros_ec_uart *ec_uart = data;
+ struct acpi_resource_uart_serialbus *sb;
+
+ switch (ares->type) {
+ case ACPI_RESOURCE_TYPE_SERIAL_BUS:
+ sb = &ares->data.uart_serial_bus;
+ if (sb->type == ACPI_RESOURCE_SERIAL_TYPE_UART) {
+ ec_uart->baudrate = sb->default_baud_rate;
+ dev_dbg(&ec_uart->serdev->dev, "Baudrate %d\n",
+ ec_uart->baudrate);
+
+ ec_uart->flowcontrol = sb->flow_control;
+ dev_dbg(&ec_uart->serdev->dev, "Flow control %d\n",
+ ec_uart->flowcontrol);
+ }
+ break;
+ default:
+ break;
+ }
+
+ return 0;
+}
+
+static int cros_ec_uart_acpi_probe(struct cros_ec_uart *ec_uart)
+{
+ LIST_HEAD(resources);
+ struct acpi_device *adev = ACPI_COMPANION(&ec_uart->serdev->dev);
+ int ret;
+
+ /* Retrieve UART ACPI info */
+ ret = acpi_dev_get_resources(adev, &resources,
+ cros_ec_uart_resource, ec_uart);
+ if (ret < 0)
+ return ret;
+
+ acpi_dev_free_resource_list(&resources);
+
+ /* Retrieve GpioInt and translate it to Linux IRQ number */
+ ret = acpi_dev_gpio_irq_get(adev, 0);
+ if (ret < 0)
+ return ret;
+
+ ec_uart->irq = ret;
+ dev_dbg(&ec_uart->serdev->dev, "IRQ number %d\n", ec_uart->irq);
+
+ return 0;
+}
+
+static const struct serdev_device_ops cros_ec_uart_client_ops = {
+ .receive_buf = cros_ec_uart_rx_bytes,
+};
+
+static int cros_ec_uart_probe(struct serdev_device *serdev)
+{
+ struct device *dev = &serdev->dev;
+ struct cros_ec_device *ec_dev;
+ struct cros_ec_uart *ec_uart;
+ int ret;
+
+ ec_uart = devm_kzalloc(dev, sizeof(*ec_uart), GFP_KERNEL);
+ if (!ec_uart)
+ return -ENOMEM;
+
+ ec_dev = devm_kzalloc(dev, sizeof(*ec_dev), GFP_KERNEL);
+ if (!ec_dev)
+ return -ENOMEM;
+
+ ec_uart->serdev = serdev;
+
+ /* Open the serial device */
+ ret = devm_serdev_device_open(dev, ec_uart->serdev);
+ if (ret) {
+ dev_err(dev, "Unable to open UART device %s",
+ dev_name(&serdev->dev));
+ return ret;
+ }
+
+ serdev_device_set_drvdata(serdev, ec_dev);
+
+ serdev_device_set_client_ops(serdev, &cros_ec_uart_client_ops);
+
+ /* Initialize wait queue */
+ init_waitqueue_head(&ec_uart->response.wait_queue);
+
+ ret = cros_ec_uart_acpi_probe(ec_uart);
+ if (ret < 0) {
+ dev_err(dev, "Failed to get ACPI info (%d)", ret);
+ return ret;
+ }
+
+ /* Set baud rate of serial device */
+ ret = serdev_device_set_baudrate(serdev, ec_uart->baudrate);
+ if (ret < 0) {
+ dev_err(dev, "Failed to set up host baud rate (%d)", ret);
+ return ret;
+ }
+
+ /* Set flow control of serial device */
+ serdev_device_set_flow_control(serdev, ec_uart->flowcontrol);
+
+ /* Initialize ec_dev for cros_ec */
+ ec_dev->phys_name = dev_name(&ec_uart->serdev->dev);
+ ec_dev->dev = dev;
+ ec_dev->priv = ec_uart;
+ ec_dev->irq = ec_uart->irq;
+ ec_dev->cmd_xfer = NULL;
+ ec_dev->pkt_xfer = cros_ec_uart_pkt_xfer;
+ ec_dev->din_size = sizeof(struct ec_host_response) +
+ sizeof(struct ec_response_get_protocol_info);
+ ec_dev->dout_size = sizeof(struct ec_host_request);
+
+ /* Register a new cros_ec device */
+ return cros_ec_register(ec_dev);
+}
+
+static void cros_ec_uart_remove(struct serdev_device *serdev)
+{
+ struct cros_ec_device *ec_dev = serdev_device_get_drvdata(serdev);
+
+ cros_ec_unregister(ec_dev);
+};
+
+static int __maybe_unused cros_ec_uart_suspend(struct device *dev)
+{
+ struct cros_ec_device *ec_dev = dev_get_drvdata(dev);
+
+ return cros_ec_suspend(ec_dev);
+}
+
+static int __maybe_unused cros_ec_uart_resume(struct device *dev)
+{
+ struct cros_ec_device *ec_dev = dev_get_drvdata(dev);
+
+ return cros_ec_resume(ec_dev);
+}
+
+static SIMPLE_DEV_PM_OPS(cros_ec_uart_pm_ops, cros_ec_uart_suspend,
+ cros_ec_uart_resume);
+
+static const struct of_device_id cros_ec_uart_of_match[] = {
+ { .compatible = "google,cros-ec-uart" },
+ {}
+};
+
+static struct serdev_device_driver cros_ec_uart_driver = {
+ .driver = {
+ .name = "cros-ec-uart",
+ .of_match_table = cros_ec_uart_of_match,
+ .pm = &cros_ec_uart_pm_ops,
+ },
+ .probe = cros_ec_uart_probe,
+ .remove = cros_ec_uart_remove,
+};
+
+module_serdev_device_driver(cros_ec_uart_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("UART interface for ChromeOS Embedded Controller");
+MODULE_AUTHOR("Bhanu Prakash Maiya <bhanumaiya@chromium.org>");
--
2.26.2
^ permalink raw reply related [flat|nested] 8+ messages in thread
end of thread, other threads:[~2020-07-15 8:20 UTC | newest]
Thread overview: 8+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-06-25 21:34 [PATCH 1/2] cros: platform/chrome: Add cros-ec-uart driver for uart support Bhanu Prakash Maiya
2020-06-25 21:34 ` [PATCH 2/2] dt-bindings: mfd: Add DT compatible string "google,cros_ec_uart" Bhanu Prakash Maiya
2020-06-26 8:42 ` Enric Balletbo i Serra
2020-06-26 0:18 ` [PATCH 1/2] cros: platform/chrome: Add cros-ec-uart driver for uart support kernel test robot
2020-06-26 8:33 ` kernel test robot
2020-07-15 7:41 Bhanu Prakash Maiya
2020-07-15 7:56 ` Greg Kroah-Hartman
2020-07-15 8:20 Bhanu Prakash Maiya
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