Re: [PATCH v8 6/7] power: cros_usbpd-charger: Add EC-based USB PD charger driver

From: Enric Balletbo i Serra
Date: Tue Apr 26 2016 - 06:47:42 EST


Hi Tomeu,

Thanks for the patch, looks good, a few comments below.

On 20/04/16 09:42, Tomeu Vizoso wrote:
Hi Sebastian,

is there any chance that you could review this patch?

Thanks,

Tomeu

On 12 April 2016 at 14:32, Tomeu Vizoso <tomeu.vizoso@xxxxxxxxxxxxx> wrote:
From: Sameer Nanda <snanda@xxxxxxxxxxxx>

This driver exposes the charger functionality in the PD EC to userspace.

Signed-off-by: Tomeu Vizoso <tomeu.vizoso@xxxxxxxxxxxxx>
Cc: Sameer Nanda <snanda@xxxxxxxxxxxx>
Cc: Benson Leung <bleung@xxxxxxxxxxxx>
Cc: Shawn Nematbakhsh <shawnn@xxxxxxxxxxxx>
---

Changes in v8: None
Changes in v7: None
Changes in v6: None
Changes in v5:
- Fix type of variable passed to do_div.

Changes in v4:
- Declare size parameters in ec_command as size_t

Changes in v3:
- Use do_div so it builds on 32bit (suggested by 0-day kbuild bot).
- Remove sysfs attributes ext_current_lim and ext_voltage_lim because
I don't know yet where they should be placed (and don't have HW to
test them).
- Remove superfluous pre-allocated buffers ec_inbuf and ec_outbuf.
- Lots of misc comments from Stephen Boyd were addressed.
- Unregister notification listener in .remove callback.

Changes in v2:
- Split out changes to cros_ec_commands.h and the helpers added to
mfd/cros_ec.h from the patch that adds the charger driver, as
suggested by Lee.
- Actually call get_ec_num_ports.

drivers/power/Kconfig | 10 +
drivers/power/Makefile | 1 +
drivers/power/cros_usbpd-charger.c | 780 +++++++++++++++++++++++++++++++++++++
3 files changed, 791 insertions(+)
create mode 100644 drivers/power/cros_usbpd-charger.c

diff --git a/drivers/power/Kconfig b/drivers/power/Kconfig
index 421770ddafa3..d096e76ed822 100644
--- a/drivers/power/Kconfig
+++ b/drivers/power/Kconfig
@@ -509,6 +509,16 @@ config AXP20X_POWER
This driver provides support for the power supply features of
AXP20x PMIC.

+config CHARGER_CROS_USB_PD
+ tristate "Chrome OS EC based USB PD charger"
+ depends on MFD_CROS_EC
+ default y

Guess you should not set default to yes here.

+ help
+ Say Y here to enable Chrome OS EC based USB PD charger driver. This
+ driver gets various bits of information about what is connected to
+ USB PD ports from the EC and converts that into power_supply
+ properties.
+
endif # POWER_SUPPLY

source "drivers/power/reset/Kconfig"
diff --git a/drivers/power/Makefile b/drivers/power/Makefile
index e46b75d448a5..c9eca1f9bfb0 100644
--- a/drivers/power/Makefile
+++ b/drivers/power/Makefile
@@ -74,3 +74,4 @@ obj-$(CONFIG_CHARGER_TPS65217) += tps65217_charger.o
obj-$(CONFIG_POWER_RESET) += reset/
obj-$(CONFIG_AXP288_FUEL_GAUGE) += axp288_fuel_gauge.o
obj-$(CONFIG_AXP288_CHARGER) += axp288_charger.o
+obj-$(CONFIG_CHARGER_CROS_USB_PD) += cros_usbpd-charger.o
diff --git a/drivers/power/cros_usbpd-charger.c b/drivers/power/cros_usbpd-charger.c
new file mode 100644
index 000000000000..e7366660c093
--- /dev/null
+++ b/drivers/power/cros_usbpd-charger.c
@@ -0,0 +1,780 @@
+/*
+ * Power supply driver for ChromeOS EC based USB PD Charger.
+ *
+ * Copyright (c) 2014 Google, Inc
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/ktime.h>
+#include <linux/module.h>
+#include <linux/mfd/cros_ec.h>
+#include <linux/mfd/cros_ec_commands.h>
+#include <linux/platform_device.h>
+#include <linux/power_supply.h>
+#include <linux/rtc.h>
+#include <linux/slab.h>
+
+#define CROS_USB_PD_MAX_PORTS 8
+#define CROS_USB_PD_MAX_LOG_ENTRIES 30
+
+#define CROS_USB_PD_LOG_UPDATE_DELAY msecs_to_jiffies(60000)
+#define CROS_USB_PD_CACHE_UPDATE_DELAY msecs_to_jiffies(500)
+
+/* Buffer + macro for building PDLOG string */
+#define BUF_SIZE 80
+#define APPEND_STRING(buf, len, str, ...) ((len) += \
+ snprintf((buf) + (len), max(BUF_SIZE - (len), 0), (str), ##__VA_ARGS__))
+
+#define CHARGER_DIR_NAME "CROS_USB_PD_CHARGER%d"
+#define CHARGER_DIR_NAME_LENGTH sizeof(CHARGER_DIR_NAME)
+
+#define MANUFACTURER_MODEL_LENGTH 32
+
+struct port_data {
+ int port_number;
+ char name[CHARGER_DIR_NAME_LENGTH];
+ char manufacturer[MANUFACTURER_MODEL_LENGTH];
+ char model_name[MANUFACTURER_MODEL_LENGTH];
+ struct power_supply *psy;
+ struct power_supply_desc psy_desc;
+ int psy_type;
+ int psy_online;
+ int psy_status;
+ int psy_current_max;
+ int psy_voltage_max_design;
+ int psy_voltage_now;
+ int psy_power_max;
+ struct charger_data *charger;
+ unsigned long last_update;
+};
+
+struct charger_data {
+ struct device *dev;
+ struct cros_ec_dev *ec_dev;
+ struct cros_ec_device *ec_device;
+ int num_charger_ports;
+ int num_registered_psy;
+ struct port_data *ports[CROS_USB_PD_MAX_PORTS];
+ struct delayed_work log_work;
+ struct workqueue_struct *log_workqueue;
+ struct notifier_block notifier;
+ bool suspended;
+};
+
+static enum power_supply_property cros_usb_pd_charger_props[] = {
+ POWER_SUPPLY_PROP_ONLINE,
+ POWER_SUPPLY_PROP_STATUS,
+ POWER_SUPPLY_PROP_CURRENT_MAX,
+ POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
+ POWER_SUPPLY_PROP_VOLTAGE_NOW,
+ POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT_MAX,
+ POWER_SUPPLY_PROP_MODEL_NAME,
+ POWER_SUPPLY_PROP_MANUFACTURER,
+};
+
+static int ec_command(struct cros_ec_dev *ec_dev, int version, int command,
+ uint8_t *outdata, size_t outsize, uint8_t *indata,
+ size_t insize)
+{
+ struct cros_ec_device *ec_device = ec_dev->ec_dev;
+ struct cros_ec_command *msg;
+ int ret;
+
+ msg = kmalloc(sizeof(*msg) + max(outsize, insize), GFP_KERNEL);
+ if (!msg)
+ return -ENOMEM;
+
+ msg->version = version;
+ msg->command = ec_dev->cmd_offset + command;
+ msg->outsize = outsize;
+ msg->insize = insize;
+
+ memcpy(msg->data, outdata, outsize);
+ ret = cros_ec_cmd_xfer_status(ec_device, msg);
+ memcpy(indata, msg->data, insize);
+
+ kfree(msg);
+
+ return ret;
+}
+
+static int set_ec_usb_pd_override_ports(struct charger_data *charger,
+ int port_num)
+{
+ struct device *dev = charger->dev;
+ struct ec_params_charge_port_override req;
+ int ret;
+
+ req.override_port = port_num;
+
+ ret = ec_command(charger->ec_dev, 0, EC_CMD_PD_CHARGE_PORT_OVERRIDE,
+ (uint8_t *)&req, sizeof(req),
+ NULL, 0);
+ if (ret < 0) {
+ dev_err(dev, "Port Override command returned 0x%x\n", ret);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int get_ec_num_ports(struct charger_data *charger, int *num_ports)
+{
+ struct device *dev = charger->dev;
+ struct ec_response_usb_pd_ports resp;
+ int ret;
+
+ *num_ports = 0;
+ ret = ec_command(charger->ec_dev, 0, EC_CMD_USB_PD_PORTS, NULL, 0,
+ (uint8_t *)&resp, sizeof(resp));
+ if (ret < 0) {
+ dev_err(dev, "Unable to query PD ports (err:0x%x)\n", ret);
+ return ret;

Generally you return -EINVAL instead of ret when ec_command fails, any reason why here is different?

+ }
+ *num_ports = resp.num_ports;
+ dev_dbg(dev, "Num ports = %d\n", *num_ports);
+
+ return 0;
+}
+
+static int get_ec_usb_pd_discovery_info(struct port_data *port)
+{
+ struct charger_data *charger = port->charger;
+ struct device *dev = charger->dev;
+ struct ec_params_usb_pd_info_request req;
+ struct ec_params_usb_pd_discovery_entry resp;
+ int ret;
+
+ req.port = port->port_number;
+
+ ret = ec_command(charger->ec_dev, 0, EC_CMD_USB_PD_DISCOVERY,
+ (uint8_t *)&req, sizeof(req),
+ (uint8_t *)&resp, sizeof(resp));
+ if (ret < 0) {
+ dev_err(dev, "Unable to query Discovery info (err:0x%x)\n",
+ ret);
+ return -EINVAL;
+ }
+
+ dev_dbg(dev, "Port %d: VID = 0x%x, PID=0x%x, PTYPE=0x%x\n",
+ port->port_number, resp.vid, resp.pid, resp.ptype);
+
+ snprintf(port->manufacturer, MANUFACTURER_MODEL_LENGTH, "%x", resp.vid);

This looks a vendor id code, generally I saw this propietry show the manufacturer name.

+ snprintf(port->model_name, MANUFACTURER_MODEL_LENGTH, "%x", resp.pid);
+
+ return 0;
+}
+
+static int get_ec_usb_pd_power_info(struct port_data *port)
+{
+ struct charger_data *charger = port->charger;
+ struct device *dev = charger->dev;
+ struct ec_params_usb_pd_power_info req;
+ struct ec_response_usb_pd_power_info resp;
+ char role_str[80];
+ int ret, last_psy_status, last_psy_type;
+
+ req.port = port->port_number;
+ ret = ec_command(charger->ec_dev, 0, EC_CMD_USB_PD_POWER_INFO,
+ (uint8_t *)&req, sizeof(req),
+ (uint8_t *)&resp, sizeof(resp));
+ if (ret < 0) {
+ dev_err(dev, "Unable to query PD power info (err:0x%x)\n", ret);
+ return -EINVAL;
+ }
+
+ last_psy_status = port->psy_status;
+ last_psy_type = port->psy_type;
+
+ switch (resp.role) {
+ case USB_PD_PORT_POWER_DISCONNECTED:
+ snprintf(role_str, sizeof(role_str), "%s", "DISCONNECTED");
+ port->psy_status = POWER_SUPPLY_STATUS_NOT_CHARGING;
+ port->psy_online = 0;
+ break;
+ case USB_PD_PORT_POWER_SOURCE:
+ snprintf(role_str, sizeof(role_str), "%s", "SOURCE");
+ port->psy_status = POWER_SUPPLY_STATUS_NOT_CHARGING;
+ port->psy_online = 0;
+ break;
+ case USB_PD_PORT_POWER_SINK:
+ snprintf(role_str, sizeof(role_str), "%s", "SINK");
+ port->psy_status = POWER_SUPPLY_STATUS_CHARGING;
+ port->psy_online = 1;
+ break;
+ case USB_PD_PORT_POWER_SINK_NOT_CHARGING:
+ snprintf(role_str, sizeof(role_str), "%s", "NOT CHARGING");
+ port->psy_status = POWER_SUPPLY_STATUS_NOT_CHARGING;
+ port->psy_online = 1;
+ break;
+ default:
+ snprintf(role_str, sizeof(role_str), "%s", "UNKNOWN");
+ dev_err(dev, "Unknown role %d\n", resp.role);
+ break;
+ }
+
+ port->psy_voltage_max_design = resp.meas.voltage_max;
+ port->psy_voltage_now = resp.meas.voltage_now;
+ port->psy_current_max = resp.meas.current_max;
+ port->psy_power_max = resp.max_power;
+
+ switch (resp.type) {
+ case USB_CHG_TYPE_BC12_SDP:
+ case USB_CHG_TYPE_VBUS:
+ port->psy_type = POWER_SUPPLY_TYPE_USB;
+ break;
+ case USB_CHG_TYPE_NONE:
+ /*
+ * For dual-role devices when we are a source, the firmware
+ * reports the type as NONE. Report such chargers as type
+ * USB_PD_DRP.
+ */
+ if (resp.role == USB_PD_PORT_POWER_SOURCE && resp.dualrole)
+ port->psy_type = POWER_SUPPLY_TYPE_USB_PD_DRP;
+ else
+ port->psy_type = POWER_SUPPLY_TYPE_USB;
+ break;
+ case USB_CHG_TYPE_PROPRIETARY:
+ port->psy_type = POWER_SUPPLY_TYPE_MAINS;
+ break;
+ case USB_CHG_TYPE_C:
+ port->psy_type = POWER_SUPPLY_TYPE_USB_TYPE_C;
+ break;
+ case USB_CHG_TYPE_BC12_DCP:
+ port->psy_type = POWER_SUPPLY_TYPE_USB_DCP;
+ break;
+ case USB_CHG_TYPE_BC12_CDP:
+ port->psy_type = POWER_SUPPLY_TYPE_USB_CDP;
+ break;
+ case USB_CHG_TYPE_PD:
+ if (resp.dualrole)
+ port->psy_type = POWER_SUPPLY_TYPE_USB_PD_DRP;
+ else
+ port->psy_type = POWER_SUPPLY_TYPE_USB_PD;
+ break;
+ case USB_CHG_TYPE_UNKNOWN:
+ /*
+ * While the EC is trying to determine the type of charger that
+ * has been plugged in, it will report the charger type as
+ * unknown. Treat this case as a dedicated charger since we
+ * don't know any better just yet. Additionally since the power
+ * capabilities are unknown, report the max current and voltage
+ * as zero.
+ */
+ port->psy_type = POWER_SUPPLY_TYPE_MAINS;
+ port->psy_voltage_max_design = 0;
+ port->psy_current_max = 0;
+ break;
+ default:
+ dev_err(dev, "Port %d: default case!\n",
+ port->port_number);
+ port->psy_type = POWER_SUPPLY_TYPE_USB;
+ }
+
+ port->psy_desc.type = port->psy_type;
+
+ dev_dbg(dev,
+ "Port %d: %s type=%d=vmax=%d vnow=%d cmax=%d clim=%d pmax=%d\n",
+ port->port_number, role_str, resp.type,
+ resp.meas.voltage_max, resp.meas.voltage_now,
+ resp.meas.current_max, resp.meas.current_lim,
+ resp.max_power);
+
+ /*
+ * If power supply type or status changed, explicitly call
+ * power_supply_changed. This results in udev event getting generated
+ * and allows user mode apps to react quicker instead of waiting for
+ * their next poll of power supply status.
+ */
+ if (last_psy_type != port->psy_type ||
+ last_psy_status != port->psy_status) {
+ dev_dbg(dev, "Port %d: Calling power_supply_changed\n",
+ port->port_number);
+ power_supply_changed(port->psy);
+ }
+
+ return 0;
+}
+
+static int get_ec_port_status(struct port_data *port, bool ratelimit)
+{
+ int ret;
+
+ if (ratelimit &&
+ time_is_after_jiffies(port->last_update +
+ CROS_USB_PD_CACHE_UPDATE_DELAY))
+ return 0;
+
+ ret = get_ec_usb_pd_power_info(port);
+ if (ret < 0)
+ return ret;
+
+ ret = get_ec_usb_pd_discovery_info(port);
+ port->last_update = jiffies;
+
+ return ret;
+}
+
+static void cros_usb_pd_charger_power_changed(struct power_supply *psy)
+{
+ struct port_data *port = power_supply_get_drvdata(psy);
+ struct charger_data *charger = port->charger;
+ struct device *dev = charger->dev;
+ int i;
+
+ dev_dbg(dev, "cros_usb_pd_charger_power_changed\n");

nit: In my opinion this debug message is not needed and doesn't add any information. It only shows that the function is called. You can usethe kernel tracing tools for that.

+ for (i = 0; i < charger->num_registered_psy; i++)
+ get_ec_port_status(charger->ports[i], false);
+}
+
+static int cros_usb_pd_charger_get_prop(struct power_supply *psy,
+ enum power_supply_property psp,
+ union power_supply_propval *val)
+{
+ struct port_data *port = power_supply_get_drvdata(psy);
+ struct charger_data *charger = port->charger;
+ struct device *dev = charger->dev;
+ int ret;
+
+
+ /* Only refresh ec_port_status for dynamic properties */
+ switch (psp) {
+ case POWER_SUPPLY_PROP_CURRENT_MAX:
+ case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
+ case POWER_SUPPLY_PROP_VOLTAGE_NOW:
+ case POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT_MAX:
+ ret = get_ec_port_status(port, true);
+ if (ret < 0) {
+ dev_err(dev, "Failed to get port status (err:0x%x)\n",
+ ret);
+ return -EINVAL;
+ }
+ break;
+ default:
+ break;
+ }
+
+ switch (psp) {
+ case POWER_SUPPLY_PROP_ONLINE:
+ val->intval = port->psy_online;
+ break;
+ case POWER_SUPPLY_PROP_STATUS:
+ val->intval = port->psy_status;
+ break;
+ case POWER_SUPPLY_PROP_CURRENT_MAX:
+ val->intval = port->psy_current_max * 1000;
+ break;
+ case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
+ val->intval = port->psy_voltage_max_design * 1000;
+ break;
+ case POWER_SUPPLY_PROP_VOLTAGE_NOW:
+ val->intval = port->psy_voltage_now * 1000;
+ break;
+ case POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT_MAX:
+ /* TODO: send a TBD host command to the EC. */
+ val->intval = 0;

If I'm not mistaken the function below sets the control limit max value, but here you always return a 0. This is confusing for me. Seems that this is not supported yet? So maybe is better remove the code related to this or store the value set in a variable meanwhile you're not able to ask the value to the EC.

+ break;
+ case POWER_SUPPLY_PROP_MODEL_NAME:
+ val->strval = port->model_name;
+ break;
+ case POWER_SUPPLY_PROP_MANUFACTURER:
+ val->strval = port->manufacturer;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int cros_usb_pd_charger_set_prop(struct power_supply *psy,
+ enum power_supply_property psp,
+ const union power_supply_propval *val)
+{
+ struct port_data *port = power_supply_get_drvdata(psy);
+ struct charger_data *charger = port->charger;
+ int port_number;
+
+ switch (psp) {
+ case POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT_MAX:
+ /*
+ * A value of -1 implies switching to battery as the power
+ * source. Any other value implies using this port as the
+ * power source.
+ */
+ port_number = val->intval;
+ if (port_number != -1)
+ port_number = port->port_number;
+ return set_ec_usb_pd_override_ports(charger, port_number);
+ default:
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static int cros_usb_pd_charger_is_writeable(struct power_supply *psy,
+ enum power_supply_property psp)
+{
+ int ret;
+
+ switch (psp) {
+ case POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT_MAX:
+ ret = 1;
+ break;
+ default:
+ ret = 0;
+ }
+
+ return ret;
+}
+
+static void cros_usb_pd_print_log_entry(struct ec_response_pd_log *r,
+ ktime_t tstamp)
+{
+ static const char * const fault_names[] = {
+ "---", "OCP", "fast OCP", "OVP", "Discharge"
+ };
+ static const char * const role_names[] = {
+ "Disconnected", "SRC", "SNK", "SNK (not charging)"
+ };
+ static const char * const chg_type_names[] = {
+ "None", "PD", "Type-C", "Proprietary",
+ "DCP", "CDP", "SDP", "Other", "VBUS"
+ };
+ int i;
+ int role_idx, type_idx;
+ const char *fault, *role, *chg_type;
+ struct usb_chg_measures *meas;
+ struct mcdp_info *minfo;
+ struct rtc_time rt;
+ u64 msecs;
+ int len = 0;
+ char buf[BUF_SIZE + 1];
+
+ /* the timestamp is the number of 1024th of seconds in the past */
+ tstamp = ktime_sub_us(tstamp,
+ (uint64_t)r->timestamp_ms << PD_LOG_TIMESTAMP_SHIFT);
+ rt = rtc_ktime_to_tm(tstamp);
+
+ switch (r->type) {
+ case PD_EVENT_MCU_CHARGE:
+ if (r->data & CHARGE_FLAGS_OVERRIDE)
+ APPEND_STRING(buf, len, "override ");
+ if (r->data & CHARGE_FLAGS_DELAYED_OVERRIDE)
+ APPEND_STRING(buf, len, "pending_override ");
+ role_idx = r->data & CHARGE_FLAGS_ROLE_MASK;
+ role = role_idx < ARRAY_SIZE(role_names) ?
+ role_names[role_idx] : "Unknown";
+ type_idx = (r->data & CHARGE_FLAGS_TYPE_MASK)
+ >> CHARGE_FLAGS_TYPE_SHIFT;
+ chg_type = type_idx < ARRAY_SIZE(chg_type_names) ?
+ chg_type_names[type_idx] : "???";
+
+ if ((role_idx == USB_PD_PORT_POWER_DISCONNECTED) ||
+ (role_idx == USB_PD_PORT_POWER_SOURCE)) {
+ APPEND_STRING(buf, len, "%s", role);
+ break;
+ }
+
+ meas = (struct usb_chg_measures *)r->payload;
+ APPEND_STRING(buf, len, "%s %s %s %dmV max %dmV / %dmA", role,
+ r->data & CHARGE_FLAGS_DUAL_ROLE ? "DRP" : "Charger",
+ chg_type,
+ meas->voltage_now,
+ meas->voltage_max,
+ meas->current_max);
+ break;
+ case PD_EVENT_ACC_RW_FAIL:
+ APPEND_STRING(buf, len, "RW signature check failed");
+ break;
+ case PD_EVENT_PS_FAULT:
+ fault = r->data < ARRAY_SIZE(fault_names) ? fault_names[r->data]
+ : "???";
+ APPEND_STRING(buf, len, "Power supply fault: %s", fault);
+ break;
+ case PD_EVENT_VIDEO_DP_MODE:
+ APPEND_STRING(buf, len, "DP mode %sabled",
+ (r->data == 1) ? "en" : "dis");
+ break;
+ case PD_EVENT_VIDEO_CODEC:
+ minfo = (struct mcdp_info *)r->payload;
+ APPEND_STRING(buf, len,
+ "HDMI info: family:%04x chipid:%04x irom:%d.%d.%d fw:%d.%d.%d",
+ MCDP_FAMILY(minfo->family),
+ MCDP_CHIPID(minfo->chipid),
+ minfo->irom.major, minfo->irom.minor,
+ minfo->irom.build, minfo->fw.major,
+ minfo->fw.minor, minfo->fw.build);
+ break;
+ default:
+ APPEND_STRING(buf, len,
+ "Event %02x (%04x) [", r->type, r->data);
+ for (i = 0; i < PD_LOG_SIZE(r->size_port); i++)
+ APPEND_STRING(buf, len, "%02x ", r->payload[i]);
+ APPEND_STRING(buf, len, "]");
+ break;
+ }
+
+ msecs = ktime_to_ms(tstamp);
+ do_div(msecs, MSEC_PER_SEC);
+ pr_info("PDLOG %d/%02d/%02d %02d:%02d:%02d.%03llu P%d %s\n",
+ rt.tm_year + 1900, rt.tm_mon + 1, rt.tm_mday,
+ rt.tm_hour, rt.tm_min, rt.tm_sec, msecs,
+ PD_LOG_PORT(r->size_port), buf);

nit: Maybe is better use a debug print level here. How often is this called?


+}
+
+static void cros_usb_pd_log_check(struct work_struct *work)
+{
+ struct charger_data *charger = container_of(to_delayed_work(work),
+ struct charger_data, log_work);
+ struct device *dev = charger->dev;
+ union {
+ struct ec_response_pd_log r;
+ uint32_t words[8]; /* space for the payload */
+ } u;
+ int ret;
+ int entries = 0;
+ ktime_t now;
+
+ if (charger->suspended) {
+ dev_dbg(dev, "Suspended...bailing out\n");
+ return;
+ }
+
+ while (entries++ < CROS_USB_PD_MAX_LOG_ENTRIES) {
+ ret = ec_command(charger->ec_dev, 0, EC_CMD_PD_GET_LOG_ENTRY,
+ NULL, 0, (uint8_t *)&u, sizeof(u));
+ now = ktime_get_real();
+ if (ret < 0) {
+ dev_dbg(dev, "Cannot get PD log %d\n", ret);
+ break;
+ }
+ if (u.r.type == PD_EVENT_NO_ENTRY)
+ break;
+
+ cros_usb_pd_print_log_entry(&u.r, now);
+ }
+
+ queue_delayed_work(charger->log_workqueue, &charger->log_work,
+ CROS_USB_PD_LOG_UPDATE_DELAY);
+}
+
+static int cros_usb_pd_ec_event(struct notifier_block *nb,
+ unsigned long queued_during_suspend, void *_notify)
+{
+ struct charger_data *charger;
+ struct device *dev;
+ struct cros_ec_device *ec_device;
+ u32 host_event;
+
+ charger = container_of(nb, struct charger_data, notifier);
+ dev = charger->dev;
+ ec_device = charger->ec_device;
+
+ host_event = cros_ec_get_host_event(ec_device);
+ if (host_event & EC_HOST_EVENT_MASK(EC_HOST_EVENT_PD_MCU)) {
+ cros_usb_pd_charger_power_changed(charger->ports[0]->psy);
+ return NOTIFY_OK;
+ }
+
+ return NOTIFY_DONE;
+}
+
+static char *charger_supplied_to[] = {"cros-usb_pd-charger"};
+
+static int cros_usb_pd_charger_probe(struct platform_device *pd)
+{
+ struct device *dev = &pd->dev;
+ struct cros_ec_dev *ec_dev = dev_get_drvdata(pd->dev.parent);
+ struct cros_ec_device *ec_device;
+ struct charger_data *charger;
+ struct port_data *port;
+ struct power_supply_desc *psy_desc;
+ struct power_supply_config psy_cfg = {};
+ int i;
+ int ret = -EINVAL;
+
+ dev_dbg(dev, "cros_usb_pd_charger_probe\n");

nit: Remove? You can use kernel tracing tools to print functions calls.

+ if (!ec_dev) {
+ WARN(1, "%s: No EC dev found\n", dev_name(dev));
+ return -EINVAL;
+ }
+
+ ec_device = ec_dev->ec_dev;
+ if (!ec_device) {
+ WARN(1, "%s: No EC device found\n", dev_name(dev));
+ return -EINVAL;
+ }
+
+ charger = devm_kzalloc(dev, sizeof(struct charger_data),
+ GFP_KERNEL);

Alignement should match with parentheses.

+ if (!charger)
+ return -ENOMEM;
+
+ charger->dev = dev;
+ charger->ec_dev = ec_dev;
+ charger->ec_device = ec_device;
+
+ platform_set_drvdata(pd, charger);
+
+ if ((get_ec_num_ports(charger, &charger->num_charger_ports) < 0) ||
+ !charger->num_charger_ports) {
+ dev_err(dev, "No charging ports found\n");
+ ret = -ENODEV;
+ goto fail;

I think you can return -ENODEV directly here, you don't need to jump to fail.

+ }
+
+ for (i = 0; i < charger->num_charger_ports; i++) {
+ port = devm_kzalloc(dev, sizeof(struct port_data), GFP_KERNEL);
+ if (!port) {
+ ret = -ENOMEM;
+ goto fail;
+ }
+
+ port->charger = charger;
+ port->port_number = i;
+ sprintf(port->name, CHARGER_DIR_NAME, i);
+
+ psy_desc = &port->psy_desc;
+ psy_desc->name = port->name;
+ psy_desc->type = POWER_SUPPLY_TYPE_USB;
+ psy_desc->get_property = cros_usb_pd_charger_get_prop;
+ psy_desc->set_property = cros_usb_pd_charger_set_prop;
+ psy_desc->property_is_writeable =
+ cros_usb_pd_charger_is_writeable;
+ psy_desc->external_power_changed =
+ cros_usb_pd_charger_power_changed;
+ psy_desc->properties = cros_usb_pd_charger_props;
+ psy_desc->num_properties = ARRAY_SIZE(
+ cros_usb_pd_charger_props);
+
+ psy_cfg.drv_data = port;
+ psy_cfg.supplied_to = charger_supplied_to;
+ psy_cfg.num_supplicants = ARRAY_SIZE(charger_supplied_to);
+
+ port->psy = power_supply_register_no_ws(dev, psy_desc,
+ &psy_cfg);

Guess you can use devm_power_supply_register_no_ws here.

+ if (IS_ERR(port->psy)) {
+ dev_err(dev, "Failed to register power supply: %ld\n",
+ PTR_ERR(port->psy));
+ continue;
+ }
+
+ charger->ports[charger->num_registered_psy++] = port;
+ }
+
+ if (!charger->num_registered_psy) {
+ ret = -ENODEV;
+ dev_err(dev, "No power supplies registered\n");
+ goto fail;
+ }
+
+ if (ec_device->mkbp_event_supported) {
+ /* Get PD events from the EC */
+ charger->notifier.notifier_call = cros_usb_pd_ec_event;
+ ret = blocking_notifier_chain_register(
+ &ec_device->event_notifier, &charger->notifier);
+ if (ret < 0)
+ dev_warn(dev, "failed to register notifier\n");
+ }
+
+ /* Retrieve PD event logs periodically */
+ INIT_DELAYED_WORK(&charger->log_work, cros_usb_pd_log_check);
+ charger->log_workqueue =
+ create_singlethread_workqueue("cros_usb_pd_log");
+ queue_delayed_work(charger->log_workqueue, &charger->log_work,
+ CROS_USB_PD_LOG_UPDATE_DELAY);
+
+ return 0;
+
+fail:
+ for (i = 0; i < charger->num_registered_psy; i++) {
+ port = charger->ports[i];
+ power_supply_unregister(port->psy);

If you use devm_power_supply_register_no_ws this is not needed since it would be called by managed resources infrastructure.

+ devm_kfree(dev, port);

Guess the managed resources infrastructure will do this for you.

+ }
+ platform_set_drvdata(pd, NULL);
+
+ return ret;
+}
+
+static int cros_usb_pd_charger_remove(struct platform_device *pd)
+{
+ struct charger_data *charger = platform_get_drvdata(pd);
+ struct port_data *port;
+ int i;
+
+ if (charger->notifier.notifier_call)
+ blocking_notifier_chain_unregister(
+ &charger->ec_device->event_notifier,
+ &charger->notifier);
+
+ for (i = 0; i < charger->num_registered_psy; i++) {
+ port = charger->ports[i];
+ power_supply_unregister(port->psy);
+ }
+ flush_delayed_work(&charger->log_work);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int cros_usb_pd_charger_resume(struct device *dev)
+{
+ struct charger_data *charger = dev_get_drvdata(dev);
+ int i;
+
+ if (!charger)
+ return 0;
+
+ charger->suspended = false;
+
+ dev_dbg(dev, "cros_usb_pd_charger_resume: updating power supplies\n");
+ for (i = 0; i < charger->num_registered_psy; i++) {
+ power_supply_changed(charger->ports[i]->psy);
+ charger->ports[i]->last_update =
+ jiffies - CROS_USB_PD_CACHE_UPDATE_DELAY;
+ }
+ queue_delayed_work(charger->log_workqueue, &charger->log_work,
+ CROS_USB_PD_LOG_UPDATE_DELAY);
+
+ return 0;
+}
+
+static int cros_usb_pd_charger_suspend(struct device *dev)
+{
+ struct charger_data *charger = dev_get_drvdata(dev);
+
+ charger->suspended = true;
+
+ flush_delayed_work(&charger->log_work);
+
+ return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(cros_usb_pd_charger_pm_ops,
+ cros_usb_pd_charger_suspend, cros_usb_pd_charger_resume);
+
+static struct platform_driver cros_usb_pd_charger_driver = {
+ .driver = {
+ .name = "cros-usb-pd-charger",
+ .pm = &cros_usb_pd_charger_pm_ops,
+ },
+ .probe = cros_usb_pd_charger_probe,
+ .remove = cros_usb_pd_charger_remove,
+};
+
+module_platform_driver(cros_usb_pd_charger_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Chrome USB PD charger");
+MODULE_ALIAS("power_supply:cros-usb-pd-charger");
--
2.5.5


Best regards,
Enric