Hi Shawn,
Thankyou for the patch!
On 29/06/2020 14:32, Shawn Guo wrote:
There could be multiple qfprom devices on some SoCs. For example, on
MSM8939, qfprom@58000 holds efuse bits for Core Power Reduction (CPR),
and qfprom@5c000 holds bits for TSENS. Registering multiple nvmem
devices with the same id results in the following failure on the second
device.
[ 1.682731] sysfs: cannot create duplicate filename '/bus/nvmem/devices/qfprom0'
[ 1.685889] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.19.107-00567-g11c887ce2838-dirty #334
[ 1.693191] Hardware name: Square, Inc. T2 Devkit (DT)
[ 1.701610] Call trace:
[ 1.706673] dump_backtrace+0x0/0x158
[ 1.708987] show_stack+0x14/0x20
[ 1.712810] dump_stack+0x98/0xbc
[ 1.716114] sysfs_warn_dup+0x60/0x78
[ 1.719401] sysfs_do_create_link_sd.isra.0+0xdc/0xe8
[ 1.723047] sysfs_create_link+0x20/0x40
[ 1.728088] bus_add_device+0x68/0x130
[ 1.732083] device_add+0x3f8/0x628
[ 1.735639] nvmem_register.part.4+0x150/0x348
[ 1.739018] devm_nvmem_register+0x4c/0xa8
[ 1.743532] qfprom_probe+0x94/0xb8
[ 1.747615] platform_drv_probe+0x50/0xa0
[ 1.750998] really_probe+0x1b8/0x298
[ 1.755164] driver_probe_device+0x58/0x100
[ 1.758810] __driver_attach+0xe0/0xe8
[ 1.762802] bus_for_each_dev+0x74/0xc8
[ 1.766622] driver_attach+0x20/0x28
[ 1.770354] bus_add_driver+0x1ac/0x218
[ 1.774175] driver_register+0x60/0x110
[ 1.777734] __platform_driver_register+0x40/0x48
[ 1.781570] qfprom_driver_init+0x18/0x20
[ 1.786416] do_one_initcall+0x5c/0x178
[ 1.790418] kernel_init_freeable+0x198/0x244
[ 1.794062] kernel_init+0x10/0x108
[ 1.798567] ret_from_fork+0x10/0x18
[ 1.802084] qcom,qfprom: probe of 5c000.qfprom failed with error -17
Signed-off-by: Shawn Guo <shawn.guo@xxxxxxxxxx>
---
drivers/nvmem/qfprom.c | 2 ++
1 file changed, 2 insertions(+)
TBH, this functionality need to go into core driver which already has
IDR to allocated ID's for nvmem providers.
Can you try this patch:
---------------------------->cut<---------------------------------diff
--git a/drivers/nvmem/core.c b/drivers/nvmem/core.c
index 927eb5f6003f..aa87bd6415ab 100644
--- a/drivers/nvmem/core.c
+++ b/drivers/nvmem/core.c
@@ -629,12 +629,18 @@ struct nvmem_device *nvmem_register(const struct
nvmem_config *config)
if (!config->no_of_node)
nvmem->dev.of_node = config->dev->of_node;
- if (config->id == -1 && config->name) {
+ switch (config->id) {
+ case NVMEM_DEVID_NONE:
dev_set_name(&nvmem->dev, "%s", config->name);
- } else {
+ break;
+ case NVMEM_DEVID_AUTO:
+ dev_set_name(&nvmem->dev, "%s%d", config->name, nvmem->id);
+ break;
+ default:
dev_set_name(&nvmem->dev, "%s%d",
config->name ? : "nvmem",
config->name ? config->id : nvmem->id);
+ break;
}
nvmem->read_only = device_property_present(config->dev,
"read-only") ||
diff --git a/drivers/nvmem/qfprom.c b/drivers/nvmem/qfprom.c
index 8a91717600be..8b425f8d847d 100644
--- a/drivers/nvmem/qfprom.c
+++ b/drivers/nvmem/qfprom.c
@@ -31,6 +31,7 @@ static struct nvmem_config econfig = {
.name = "qfprom",
.stride = 1,
.word_size = 1,
+ .id = NVMEM_DEVID_AUTO,
.reg_read = qfprom_reg_read,
};
diff --git a/include/linux/nvmem-provider.h b/include/linux/nvmem-provider.h
index 6d6f8e5d24c9..06409a6c40bc 100644
--- a/include/linux/nvmem-provider.h
+++ b/include/linux/nvmem-provider.h
@@ -27,6 +27,9 @@ enum nvmem_type {
NVMEM_TYPE_BATTERY_BACKED,
};
+#define NVMEM_DEVID_NONE (-1)
+#define NVMEM_DEVID_AUTO (-2)
+
/**
* struct nvmem_config - NVMEM device configuration
*
---------------------------->cut<---------------------------------
Thanks,
srini
diff --git a/drivers/nvmem/qfprom.c b/drivers/nvmem/qfprom.c
index 8a91717600be..ceb837e861d8 100644
--- a/drivers/nvmem/qfprom.c
+++ b/drivers/nvmem/qfprom.c
@@ -40,6 +40,7 @@ static int qfprom_probe(struct platform_device *pdev)
struct resource *res;
struct nvmem_device *nvmem;
struct qfprom_priv *priv;
+ static int id;
priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
@@ -52,6 +53,7 @@ static int qfprom_probe(struct platform_device *pdev)
econfig.size = resource_size(res);
econfig.dev = dev;
+ econfig.id = id++;
econfig.priv = priv;
nvmem = devm_nvmem_register(dev, &econfig);
