power: supply: sbs-charger: Support multiple devices

[ Upstream commit 3ec6002 ]

If we have 2 instances of sbs-charger in the DTS, the driver probe for the second instance will fail:

[    8.012874] sbs-battery 18-000b: sbs-battery: battery gas gauge device registered
[    8.039094] sbs-charger 18-0009: ltc4100: smart charger device registered
[    8.112911] sbs-battery 20-000b: sbs-battery: battery gas gauge device registered
[    8.134533] sysfs: cannot create duplicate filename '/class/power_supply/sbs-charger'
[    8.143871] CPU: 3 PID: 295 Comm: systemd-udevd Tainted: G           O      5.10.147 torvalds#22
[    8.151974] Hardware name: ALE AMB (DT)
[    8.155828] Call trace:
[    8.158292]  dump_backtrace+0x0/0x1d4
[    8.161960]  show_stack+0x18/0x6c
[    8.165280]  dump_stack+0xcc/0x128
[    8.168687]  sysfs_warn_dup+0x60/0x7c
[    8.172353]  sysfs_do_create_link_sd+0xf0/0x100
[    8.176886]  sysfs_create_link+0x20/0x40
[    8.180816]  device_add+0x270/0x7a4
[    8.184311]  __power_supply_register+0x304/0x560
[    8.188930]  devm_power_supply_register+0x54/0xa0
[    8.193644]  sbs_probe+0xc0/0x214 [sbs_charger]
[    8.198183]  i2c_device_probe+0x2dc/0x2f4
[    8.202196]  really_probe+0xf0/0x510
[    8.205774]  driver_probe_device+0xfc/0x160
[    8.209960]  device_driver_attach+0xc0/0xcc
[    8.214146]  __driver_attach+0xc0/0x170
[    8.218002]  bus_for_each_dev+0x74/0xd4
[    8.221862]  driver_attach+0x24/0x30
[    8.225444]  bus_add_driver+0x148/0x250
[    8.229283]  driver_register+0x78/0x130
[    8.233140]  i2c_register_driver+0x4c/0xe0
[    8.237250]  sbs_driver_init+0x20/0x1000 [sbs_charger]
[    8.242424]  do_one_initcall+0x50/0x1b0
[    8.242434]  do_init_module+0x44/0x230
[    8.242438]  load_module+0x2200/0x27c0
[    8.242442]  __do_sys_finit_module+0xa8/0x11c
[    8.242447]  __arm64_sys_finit_module+0x20/0x30
[    8.242457]  el0_svc_common.constprop.0+0x64/0x154
[    8.242464]  do_el0_svc+0x24/0x8c
[    8.242474]  el0_svc+0x10/0x20
[    8.242481]  el0_sync_handler+0x108/0x114
[    8.242485]  el0_sync+0x180/0x1c0
[    8.243847] sbs-charger 20-0009: Failed to register power supply
[    8.287934] sbs-charger: probe of 20-0009 failed with error -17

This is mainly because the "name" field of power_supply_desc is a constant.
This patch fixes the issue by reusing the same approach as sbs-battery.
With this patch, the result is:
[    7.819532] sbs-charger 18-0009: ltc4100: smart charger device registered
[    7.825305] sbs-battery 18-000b: sbs-battery: battery gas gauge device registered
[    7.887423] sbs-battery 20-000b: sbs-battery: battery gas gauge device registered
[    7.893501] sbs-charger 20-0009: ltc4100: smart charger device registered

Signed-off-by: Fabien Proriol <[email protected]>
Signed-off-by: Sebastian Reichel <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>

Author: Fabien Proriol

drivers/power/supply/sbs-charger.c

@@ -154,8 +154,7 @@ static const struct regmap_config sbs_regmap = {
 	.val_format_endian = REGMAP_ENDIAN_LITTLE, /* since based on SMBus */
 };
 
-static const struct power_supply_desc sbs_desc = {
-	.name = "sbs-charger",
+static const struct power_supply_desc sbs_default_desc = {
 	.type = POWER_SUPPLY_TYPE_MAINS,
 	.properties = sbs_properties,
 	.num_properties = ARRAY_SIZE(sbs_properties),
@@ -165,9 +164,20 @@ static const struct power_supply_desc sbs_desc = {
 static int sbs_probe(struct i2c_client *client)
 {
 	struct power_supply_config psy_cfg = {};
+	struct power_supply_desc *sbs_desc;
 	struct sbs_info *chip;
 	int ret, val;
 
+	sbs_desc = devm_kmemdup(&client->dev, &sbs_default_desc,
+				sizeof(*sbs_desc), GFP_KERNEL);
+	if (!sbs_desc)
+		return -ENOMEM;
+
+	sbs_desc->name = devm_kasprintf(&client->dev, GFP_KERNEL, "sbs-%s",
+					dev_name(&client->dev));
+	if (!sbs_desc->name)
+		return -ENOMEM;
+
 	chip = devm_kzalloc(&client->dev, sizeof(struct sbs_info), GFP_KERNEL);
 	if (!chip)
 		return -ENOMEM;
@@ -191,7 +201,7 @@ static int sbs_probe(struct i2c_client *client)
 		return dev_err_probe(&client->dev, ret, "Failed to get device status\n");
 	chip->last_state = val;
 
-	chip->power_supply = devm_power_supply_register(&client->dev, &sbs_desc, &psy_cfg);
+	chip->power_supply = devm_power_supply_register(&client->dev, sbs_desc, &psy_cfg);
 	if (IS_ERR(chip->power_supply))
 		return dev_err_probe(&client->dev, PTR_ERR(chip->power_supply),
 				     "Failed to register power supply\n");