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authorHeikki Krogerus <heikki.krogerus@linux.intel.com>2019-02-13 19:36:55 +0300
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2019-02-14 10:48:44 +0100
commita043ad87a78f9cfb5ccd80f448e4e76b50546ad2 (patch)
treec00689312b38fd520d8f924b0832261a144334ca /drivers/usb
parentusb: typec: tcpm: Remove unused functions (diff)
downloadlinux-dev-a043ad87a78f9cfb5ccd80f448e4e76b50546ad2.tar.xz
linux-dev-a043ad87a78f9cfb5ccd80f448e4e76b50546ad2.zip
usb: typec: tps6598x: Check mode of operation
To prevent loading of the driver when the PD controller is still in some operational mode that the driver does not support, checking the mode in driver probe callback function. TI PD controllers may be in undefined mode of operation for example when the application code (firmware) is completely missing. Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb')
-rw-r--r--drivers/usb/typec/tps6598x.c53
1 files changed, 49 insertions, 4 deletions
diff --git a/drivers/usb/typec/tps6598x.c b/drivers/usb/typec/tps6598x.c
index 1c0033ad8738..9947c87d2a1e 100644
--- a/drivers/usb/typec/tps6598x.c
+++ b/drivers/usb/typec/tps6598x.c
@@ -14,6 +14,8 @@
#include <linux/usb/typec.h>
/* Register offsets */
+#define TPS_REG_VID 0x00
+#define TPS_REG_MODE 0x03
#define TPS_REG_CMD1 0x08
#define TPS_REG_DATA1 0x09
#define TPS_REG_INT_EVENT1 0x14
@@ -66,6 +68,20 @@ struct tps6598x_rx_identity_reg {
#define TPS_TASK_TIMEOUT 1
#define TPS_TASK_REJECTED 3
+enum {
+ TPS_MODE_APP,
+ TPS_MODE_BOOT,
+ TPS_MODE_BIST,
+ TPS_MODE_DISC,
+};
+
+static const char *const modes[] = {
+ [TPS_MODE_APP] = "APP ",
+ [TPS_MODE_BOOT] = "BOOT",
+ [TPS_MODE_BIST] = "BIST",
+ [TPS_MODE_DISC] = "DISC",
+};
+
/* Unrecognized commands will be replaced with "!CMD" */
#define INVALID_CMD(_cmd_) (_cmd_ == 0x444d4321)
@@ -384,6 +400,32 @@ err_unlock:
return IRQ_HANDLED;
}
+static int tps6598x_check_mode(struct tps6598x *tps)
+{
+ char mode[5] = { };
+ int ret;
+
+ ret = tps6598x_read32(tps, TPS_REG_MODE, (void *)mode);
+ if (ret)
+ return ret;
+
+ switch (match_string(modes, ARRAY_SIZE(modes), mode)) {
+ case TPS_MODE_APP:
+ return 0;
+ case TPS_MODE_BOOT:
+ dev_warn(tps->dev, "dead-battery condition\n");
+ return 0;
+ case TPS_MODE_BIST:
+ case TPS_MODE_DISC:
+ default:
+ dev_err(tps->dev, "controller in unsupported mode \"%s\"\n",
+ mode);
+ break;
+ }
+
+ return -ENODEV;
+}
+
static const struct regmap_config tps6598x_regmap_config = {
.reg_bits = 8,
.val_bits = 8,
@@ -409,10 +451,8 @@ static int tps6598x_probe(struct i2c_client *client)
if (IS_ERR(tps->regmap))
return PTR_ERR(tps->regmap);
- ret = tps6598x_read32(tps, 0, &vid);
- if (ret < 0)
- return ret;
- if (!vid)
+ ret = tps6598x_read32(tps, TPS_REG_VID, &vid);
+ if (ret < 0 || !vid)
return -ENODEV;
/*
@@ -425,6 +465,11 @@ static int tps6598x_probe(struct i2c_client *client)
if (i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
tps->i2c_protocol = true;
+ /* Make sure the controller has application firmware running */
+ ret = tps6598x_check_mode(tps);
+ if (ret)
+ return ret;
+
ret = tps6598x_read32(tps, TPS_REG_STATUS, &status);
if (ret < 0)
return ret;