在 2024/8/9 13:44, Krzysztof Kozlowski 写道:
On 09/08/2024 02:53, Shawn Lin wrote:
在 2024/8/8 18:36, Krzysztof Kozlowski 写道:
On 08/08/2024 05:52, Shawn Lin wrote:
RK3576 contains a UFS controller, add init support fot it.
Signed-off-by: Shawn Lin <shawn.lin@xxxxxxxxxxxxxx>
...
+ err = clk_prepare_enable(host->ref_out_clk);
+ if (err)
+ return dev_err_probe(dev, err, "failed to enable ref out clock\n");
+
+ host->rst_gpio = devm_gpiod_get(&pdev->dev, "reset", GPIOD_OUT_LOW);
+ if (IS_ERR(host->rst_gpio)) {
+ dev_err_probe(&pdev->dev, PTR_ERR(host->rst_gpio),
+ "invalid reset-gpios property in node\n");
+ err = PTR_ERR(host->rst_gpio);
No. Look at your code above - you have return dev_err_probe, so logical
is that the syntax is err = dev_err_probe. Don't over-complicate the code.
Anyway, this is suspicious. You already have resets with four resets
(!!!) and you claim you have fifth reset - GPIO? This looks just wrong,
like you represent some properties which do not belong here.
Thanks for the feadback.
Yes, we have 4 resets for controller, and one gpio to reset the
device. It happened to be called reset-gpios in DT but can be
any name if you like it to be. I added reset-gpios as a required one
listed in dt-bindings file, in patch 2.
Then explain in the bindings what this reset-gpios is for.
Got it.
> Also, why do you leave the device in the reset state? Logical one
means
> - reset is asserted. This applies to ufs_rockchip_device_reset() as >
well
> - that's just wrong code.
No, I tested it in linux-net and the output is HIGH, and leave the
device in active state.
In dts, we add:
reset-gpios = <&gpio4 RK_PD0 GPIO_ACTIVE_HIGH>;
? Don't use random values, what is type of the reset line?
so gpiod_set_value_cansleep(host->rst_gpio, 1) -> output HIGH for
gpio4_d0. Based on your comment, we should change the dts to use
GPIO_ACTIVE_LOW and then gpiod_set_value_cansleep（host->rst_gpio, 0）
Both can work, however IMO, isn't logical one means HIGH level in line
more human readable?
You mix logical level and line level.
If this is reset GPIO, then 1 means asserted so your code is bogus.
Maybe the the line is active low?
Yes, I mix the them. Will change to use active-low.
Thanks.
Where is your DTS so we can validate it?
Will add it in the next version, as now the rk3576.dtsi is under
reviewed and UFS node was not added. So I was afraid to interfere
with that patch and just wanted to add incremental patch once
rk3576.dtsi got merged.
Best regards,
Krzysztof
Best regards,
Krzysztof
