[PATCH v2 7/8] platform/chrome: Register USB PD charger device

From: Tomeu Vizoso
Date: Fri Feb 12 2016 - 07:58:21 EST


Check if a EC considers EC_CMD_USB_PD_PORTS a valid command and register
a USB PD charger device if so. This check is needed for older versions
of the ChromeOS EC firmware that don't support the EC_CMD_GET_FEATURES
command.

Signed-off-by: Tomeu Vizoso <tomeu.vizoso@xxxxxxxxxxxxx>
---

Changes in v2:
- Move cros_ec_usb_pd_charger_register into cros_ec_dev.c

drivers/platform/chrome/cros_ec_dev.c | 44 +++++++++++++++++++++++++++++++++++
1 file changed, 44 insertions(+)

diff --git a/drivers/platform/chrome/cros_ec_dev.c b/drivers/platform/chrome/cros_ec_dev.c
index d45cd254ed1c..a66d52539f3f 100644
--- a/drivers/platform/chrome/cros_ec_dev.c
+++ b/drivers/platform/chrome/cros_ec_dev.c
@@ -22,6 +22,7 @@
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/uaccess.h>
+#include <linux/mfd/core.h>

#include "cros_ec_dev.h"

@@ -87,6 +88,29 @@ exit:
return ret;
}

+static int cros_ec_has_cmd_usb_pd_ports(struct cros_ec_dev *ec)
+{
+ struct cros_ec_command *msg;
+ int ret;
+
+ msg = kmalloc(sizeof(*msg) + sizeof(struct ec_response_usb_pd_ports),
+ GFP_KERNEL);
+ if (!msg)
+ return -ENOMEM;
+
+ msg->version = 0;
+ msg->command = EC_CMD_USB_PD_PORTS + ec->cmd_offset;
+ msg->insize = sizeof(struct ec_response_usb_pd_ports);
+ msg->outsize = 0;
+
+ ret = cros_ec_cmd_xfer(ec->ec_dev, msg);
+ ret = ret >= 0 && msg->result == EC_RES_SUCCESS;
+
+ kfree(msg);
+
+ return ret;
+}
+
/* Device file ops */
static int ec_device_open(struct inode *inode, struct file *filp)
{
@@ -217,6 +241,13 @@ static void __remove(struct device *dev)
kfree(ec);
}

+static const struct mfd_cell cros_usb_pd_charger_devs[] = {
+ {
+ .name = "cros-usb-pd-charger",
+ .id = -1,
+ },
+};
+
static int ec_device_probe(struct platform_device *pdev)
{
int retval = -ENOMEM;
@@ -269,8 +300,21 @@ static int ec_device_probe(struct platform_device *pdev)
goto dev_reg_failed;
}

+ /* check whether this EC instance has the PD charge manager */
+ if (cros_ec_has_cmd_usb_pd_ports(ec)) {
+ retval = mfd_add_devices(dev, 0, cros_usb_pd_charger_devs,
+ ARRAY_SIZE(cros_usb_pd_charger_devs),
+ NULL, 0, NULL);
+ if (retval) {
+ dev_err(dev, "failed to add usb-pd-charger device\n");
+ goto pd_reg_failed;
+ }
+ }
+
return 0;

+pd_reg_failed:
+ put_device(&ec->class_dev);
dev_reg_failed:
set_named_failed:
dev_set_drvdata(dev, NULL);
--
2.5.0