[3/4] pinctrl: mcp23s08: spi: Add HW address to gpio_chip.label

Message ID 03c5ea4d98804e4ea6b0927e5bf103106e438142.1516997103.git.jan.kundrat@cesnet.cz
State New
Headers show
Series
  • Improvements for MCP23Sxx chips
Related show

Commit Message

Jan Kundrát Jan. 26, 2018, 7:16 p.m.
When several devices are sharing one hardware SPI CS, there is no visual
clue in `lsgpio` or in /sys/kernel/debug/gpio about which one is which
one. Stuff depends on the enumeration order, and therefore lower chip
addresses always go first, but that's just an implementation detail.
This change includes the device-specific address in the debug output:

  gpiochip4: GPIOs 464-479, parent: spi/spi1.1, mcp23s17.2, can sleep:
  gpiochip3: GPIOs 480-495, parent: spi/spi1.1, mcp23s17.1, can sleep:

Signed-off-by: Jan Kundrát <jan.kundrat@cesnet.cz>
---
 drivers/pinctrl/pinctrl-mcp23s08.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

Comments

Linus Walleij Feb. 7, 2018, 1:44 p.m. | #1
On Fri, Jan 26, 2018 at 8:16 PM, Jan Kundrát <jan.kundrat@cesnet.cz> wrote:

> When several devices are sharing one hardware SPI CS, there is no visual
> clue in `lsgpio` or in /sys/kernel/debug/gpio about which one is which
> one. Stuff depends on the enumeration order, and therefore lower chip
> addresses always go first, but that's just an implementation detail.
> This change includes the device-specific address in the debug output:
>
>   gpiochip4: GPIOs 464-479, parent: spi/spi1.1, mcp23s17.2, can sleep:
>   gpiochip3: GPIOs 480-495, parent: spi/spi1.1, mcp23s17.1, can sleep:
>
> Signed-off-by: Jan Kundrát <jan.kundrat@cesnet.cz>

Patch applied.

Yours,
Linus Walleij
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Patch

diff --git a/drivers/pinctrl/pinctrl-mcp23s08.c b/drivers/pinctrl/pinctrl-mcp23s08.c
index 8dc758bacdd1..c76c9d4b26c9 100644
--- a/drivers/pinctrl/pinctrl-mcp23s08.c
+++ b/drivers/pinctrl/pinctrl-mcp23s08.c
@@ -789,6 +789,7 @@  static int mcp23s08_probe_one(struct mcp23s08 *mcp, struct device *dev,
 	int status, ret;
 	bool mirror = false;
 	struct regmap_config *one_regmap_config = NULL;
+	int raw_chip_address = (addr & ~0x40) >> 1;
 
 	mutex_init(&mcp->lock);
 
@@ -817,7 +818,8 @@  static int mcp23s08_probe_one(struct mcp23s08 *mcp, struct device *dev,
 					sizeof(struct regmap_config), GFP_KERNEL);
 			mcp->reg_shift = 0;
 			mcp->chip.ngpio = 8;
-			mcp->chip.label = "mcp23s08";
+			mcp->chip.label = devm_kasprintf(dev, GFP_KERNEL,
+					"mcp23s08.%d", raw_chip_address);
 			break;
 		case MCP_TYPE_S17:
 			one_regmap_config =
@@ -825,13 +827,14 @@  static int mcp23s08_probe_one(struct mcp23s08 *mcp, struct device *dev,
 					sizeof(struct regmap_config), GFP_KERNEL);
 			mcp->reg_shift = 1;
 			mcp->chip.ngpio = 16;
-			mcp->chip.label = "mcp23s17";
+			mcp->chip.label = devm_kasprintf(dev, GFP_KERNEL,
+					"mcp23s17.%d", raw_chip_address);
 			break;
 		}
 		if (!one_regmap_config)
 			return -ENOMEM;
 
-		one_regmap_config->name = devm_kasprintf(dev, GFP_KERNEL, "%d", (addr & ~0x40) >> 1);
+		one_regmap_config->name = devm_kasprintf(dev, GFP_KERNEL, "%d", raw_chip_address);
 		mcp->regmap = devm_regmap_init(dev, &mcp23sxx_spi_regmap, mcp,
 					       one_regmap_config);
 		break;