[PATCH 08/18] serial: max310x: use separate regmap name for each port

From: Hugo Villeneuve
Date: Wed Jan 17 2024 - 17:39:33 EST


From: Hugo Villeneuve <hvilleneuve@xxxxxxxxxxxx>

Use a separate regmap name for each port so they can each have their own
debugfs entry, allowing to access each port registers independently.

For example, a four channels/ports device like the MAX14830 will have four
entries in its regmap debugfs:

$ find /sys/kernel/debug/regmap -type d | grep spi0.0
/sys/kernel/debug/regmap/spi0.0-port0
/sys/kernel/debug/regmap/spi0.0-port1
/sys/kernel/debug/regmap/spi0.0-port2
/sys/kernel/debug/regmap/spi0.0-port3

Cc: Jan Kundrát <jan.kundrat@xxxxxxxxx>
Link: https://lore.kernel.org/all/77f101f1-897d-4e6d-a8fd-27b818caf768@xxxxxxxxx/
Signed-off-by: Hugo Villeneuve <hvilleneuve@xxxxxxxxxxxx>

---

I didn't put again Jan Kundrát's Reviewed-by and Tested-by tags since this
version has modifications compared to the original one.
---
drivers/tty/serial/max310x.c | 17 +++++++++++++++++
1 file changed, 17 insertions(+)

diff --git a/drivers/tty/serial/max310x.c b/drivers/tty/serial/max310x.c
index 6549eee4f6a6..d6219077d23c 100644
--- a/drivers/tty/serial/max310x.c
+++ b/drivers/tty/serial/max310x.c
@@ -1486,6 +1486,19 @@ static struct regmap_config regcfg = {
.max_raw_write = MAX310X_FIFO_SIZE,
};

+static const char *max310x_regmap_name(u8 port_id)
+{
+ switch (port_id) {
+ case 0: return "port0";
+ case 1: return "port1";
+ case 2: return "port2";
+ case 3: return "port3";
+ default:
+ WARN_ON(true);
+ return NULL;
+ }
+}
+
#ifdef CONFIG_SPI_MASTER
static int max310x_spi_extended_reg_enable(struct device *dev, bool enable)
{
@@ -1521,6 +1534,8 @@ static int max310x_spi_probe(struct spi_device *spi)

for (i = 0; i < devtype->nr; i++) {
u8 port_mask = i * 0x20;
+
+ regcfg.name = max310x_regmap_name(i);
regcfg.read_flag_mask = port_mask;
regcfg.write_flag_mask = port_mask | MAX310X_WRITE_BIT;
regmaps[i] = devm_regmap_init_spi(spi, &regcfg);
@@ -1620,6 +1635,7 @@ static int max310x_i2c_probe(struct i2c_client *client)
client->addr, devtype->slave_addr.min,
devtype->slave_addr.max);

+ regcfg_i2c.name = max310x_regmap_name(0);
regmaps[0] = devm_regmap_init_i2c(client, &regcfg_i2c);

for (i = 1; i < devtype->nr; i++) {
@@ -1628,6 +1644,7 @@ static int max310x_i2c_probe(struct i2c_client *client)
client->adapter,
port_addr);

+ regcfg_i2c.name = max310x_regmap_name(i);
regmaps[i] = devm_regmap_init_i2c(port_client, &regcfg_i2c);
}

--
2.39.2