Re: [PATCH 1/3] net: davicom: dm9000: switch to using gpiod API

From: Paul Cercueil
Date: Fri Nov 18 2022 - 10:34:05 EST


Hi Dmitry,

Le mar. 6 sept. 2022 à 13:49:20 -0700, Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx> a écrit :
This patch switches the driver away from legacy gpio/of_gpio API to
gpiod API, and removes use of of_get_named_gpio_flags() which I want to
make private to gpiolib.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>
---
drivers/net/ethernet/davicom/dm9000.c | 26 ++++++++++++++------------
1 file changed, 14 insertions(+), 12 deletions(-)

diff --git a/drivers/net/ethernet/davicom/dm9000.c b/drivers/net/ethernet/davicom/dm9000.c
index 77229e53b04e..c85a6ebd79fc 100644
--- a/drivers/net/ethernet/davicom/dm9000.c
+++ b/drivers/net/ethernet/davicom/dm9000.c
@@ -28,8 +28,7 @@
#include <linux/irq.h>
#include <linux/slab.h>
#include <linux/regulator/consumer.h>
-#include <linux/gpio.h>
-#include <linux/of_gpio.h>
+#include <linux/gpio/consumer.h>

#include <asm/delay.h>
#include <asm/irq.h>
@@ -1421,8 +1420,7 @@ dm9000_probe(struct platform_device *pdev)
int iosize;
int i;
u32 id_val;
- int reset_gpios;
- enum of_gpio_flags flags;
+ struct gpio_desc *reset_gpio;
struct regulator *power;
bool inv_mac_addr = false;
u8 addr[ETH_ALEN];
@@ -1442,20 +1440,24 @@ dm9000_probe(struct platform_device *pdev)
dev_dbg(dev, "regulator enabled\n");
}

- reset_gpios = of_get_named_gpio_flags(dev->of_node, "reset-gpios", 0,
- &flags);
- if (gpio_is_valid(reset_gpios)) {
- ret = devm_gpio_request_one(dev, reset_gpios, flags,
- "dm9000_reset");
+ reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
+ ret = PTR_ERR_OR_ZERO(reset_gpio);
+ if (ret) {
+ dev_err(dev, "failed to request reset gpio: %d\n", ret);
+ goto out_regulator_disable;
+ }
+
+ if (reset_gpio) {
+ ret = gpiod_set_consumer_name(reset_gpio, "dm9000_reset");
if (ret) {
- dev_err(dev, "failed to request reset gpio %d: %d\n",
- reset_gpios, ret);
+ dev_err(dev, "failed to set reset gpio name: %d\n",
+ ret);
goto out_regulator_disable;
}

/* According to manual PWRST# Low Period Min 1ms */
msleep(2);
- gpio_set_value(reset_gpios, 1);
+ gpiod_set_value_cansleep(reset_gpio, 0);

Why is that 1 magically turned into a 0?

On my CI20 board I can't get the DM9000 chip to probe correctly with this patch (it fails to read the ID).
If I revert this patch then everything works fine.

Cheers,
-Paul

/* Needs 3ms to read eeprom when PWRST is deasserted */
msleep(4);
}
--
2.37.2.789.g6183377224-goog