From: "H. Nikolaus Schaller" <hns@goldelico.com>
To: Sven Van Asbroeck <thesven73@gmail.com>
Cc: Linus Walleij <linus.walleij@linaro.org>,
Mark Brown <broonie@kernel.org>,
kernel list <linux-kernel@vger.kernel.org>,
Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
Discussions about the Letux Kernel
<letux-kernel@openphoenux.org>
Subject: Re: [BUG] SPI broken for SPI based panel drivers
Date: Tue, 1 Dec 2020 09:59:43 +0100 [thread overview]
Message-ID: <4AC29229-9542-4E77-B993-217E29C7E209@goldelico.com> (raw)
In-Reply-To: <CAGngYiXgc_m2A7Wihxuhzm-u4qH-JZgxHjke653zvyT45jMU7Q@mail.gmail.com>
Hi Sven,
> Am 30.11.2020 um 21:13 schrieb Sven Van Asbroeck <thesven73@gmail.com>:
>
> Hi Nikolaus, thank you for reaching out !
>
> On Mon, Nov 30, 2020 at 2:06 PM H. Nikolaus Schaller <hns@goldelico.com> wrote:
>>
>> But reverting your patch brings back the display. So it appears as if it does not
>> fix a breakage, rather breaks a previously working setup.
>
> The patch in question fixes an important breakage: before the patch, literally
> hundreds of SPI drivers no longer worked - only if the SPI bus master
> driver was using gpio descriptors.
>
> We knew that there was a chance that our fix would break something else.
> But hopefully "it fixes more than it breaks"
Then it should not have been applied to mainline but fully worked out and tested.
>
>>
>> What should we do?
>>
>
> Can you try the following patch ?
Unfortunately it doesn't seem to fix it. And combined with the second proposed fix also not.
BR and thanks,
Nikolaus
my combined change:
diff --git a/drivers/spi/spi-gpio.c b/drivers/spi/spi-gpio.c
index 7ceb0ba27b755c..ec2da62716a279 100644
--- a/drivers/spi/spi-gpio.c
+++ b/drivers/spi/spi-gpio.c
@@ -208,8 +208,8 @@ static void spi_gpio_chipselect(struct spi_device *spi, int is_active)
if (spi_gpio->cs_gpios) {
struct gpio_desc *cs = spi_gpio->cs_gpios[spi->chip_select];
- /* SPI chip selects are normally active-low */
- gpiod_set_value_cansleep(cs, (spi->mode & SPI_CS_HIGH) ? is_active : !is_active);
+ /* SPI chip select polarity handled by gpiolib*/
+ gpiod_set_value_cansleep(cs, is_active);
}
}
@@ -226,8 +226,7 @@ static int spi_gpio_setup(struct spi_device *spi)
if (spi_gpio->cs_gpios) {
cs = spi_gpio->cs_gpios[spi->chip_select];
if (!spi->controller_state && cs)
- status = gpiod_direction_output(cs,
- !(spi->mode & SPI_CS_HIGH));
+ status = gpiod_direction_output(cs, false);
}
if (!status)
next prev parent reply other threads:[~2020-12-01 9:24 UTC|newest]
Thread overview: 42+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-11-30 19:03 [BUG] SPI broken for SPI based panel drivers H. Nikolaus Schaller
2020-11-30 20:13 ` Sven Van Asbroeck
2020-11-30 20:22 ` Sven Van Asbroeck
2020-12-01 8:59 ` H. Nikolaus Schaller [this message]
2020-12-01 12:16 ` Mark Brown
2020-12-01 14:05 ` H. Nikolaus Schaller
2020-12-01 14:20 ` Linus Walleij
2020-12-01 14:34 ` Sven Van Asbroeck
2020-12-01 14:35 ` H. Nikolaus Schaller
2020-12-01 15:52 ` Sven Van Asbroeck
2020-12-01 16:46 ` H. Nikolaus Schaller
2020-12-01 16:10 ` Sven Van Asbroeck
2020-12-01 16:39 ` H. Nikolaus Schaller
2020-12-01 16:53 ` Sven Van Asbroeck
2020-12-01 17:10 ` H. Nikolaus Schaller
2020-12-01 18:43 ` Sven Van Asbroeck
2020-12-02 12:19 ` Mark Brown
2020-12-04 10:08 ` H. Nikolaus Schaller
2020-12-04 13:46 ` Sven Van Asbroeck
2020-12-04 16:49 ` H. Nikolaus Schaller
2020-12-04 19:19 ` Sven Van Asbroeck
2020-12-04 21:31 ` H. Nikolaus Schaller
2020-12-05 0:25 ` Linus Walleij
2020-12-05 7:04 ` H. Nikolaus Schaller
2020-12-09 8:04 ` Andreas Kemnade
2020-12-09 8:40 ` H. Nikolaus Schaller
2020-12-09 8:38 ` Linus Walleij
2020-12-09 8:45 ` H. Nikolaus Schaller
2020-12-01 22:51 ` Linus Walleij
2020-12-01 16:44 ` [Letux-kernel] " Andreas Kemnade
2020-12-01 16:51 ` H. Nikolaus Schaller
2020-12-01 16:52 ` H. Nikolaus Schaller
2020-12-01 16:55 ` Sven Van Asbroeck
2020-12-01 16:20 ` Mark Brown
2020-12-01 16:41 ` H. Nikolaus Schaller
2020-12-01 17:11 ` Mark Brown
2020-12-01 12:41 ` Sven Van Asbroeck
2020-12-01 13:32 ` H. Nikolaus Schaller
2020-12-01 14:08 ` Sven Van Asbroeck
2020-12-01 15:33 ` Mark Brown
2020-12-05 20:57 ` Pavel Machek
2020-12-07 13:43 ` Mark Brown
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