Hi Maxime,
On Mon, 2020-02-24 at 10:06 +0100, Maxime Ripard wrote:
The reset-simple code lacks a reset callback that is still pretty easy to implement. The only real thing to consider is the delay needed for a device to be reset, so let's expose that as part of the reset-simple driver data.
Cc: Philipp Zabel p.zabel@pengutronix.de Signed-off-by: Maxime Ripard maxime@cerno.tech
This shoulod be done in such a way that simple reset drivers which do not set the reset delay continue to return -ENOTSUPP from reset_control_reset().
drivers/reset/reset-simple.c | 21 +++++++++++++++++++++ include/linux/reset/reset-simple.h | 4 ++++ 2 files changed, 25 insertions(+)
diff --git a/drivers/reset/reset-simple.c b/drivers/reset/reset-simple.c index c854aa351640..7a8c56512ae9 100644 --- a/drivers/reset/reset-simple.c +++ b/drivers/reset/reset-simple.c @@ -11,6 +11,7 @@
- Maxime Ripard maxime.ripard@free-electrons.com
*/
+#include <linux/delay.h> #include <linux/device.h> #include <linux/err.h> #include <linux/io.h> @@ -63,6 +64,25 @@ static int reset_simple_deassert(struct reset_controller_dev *rcdev, return reset_simple_update(rcdev, id, false); }
+static int reset_simple_reset(struct reset_controller_dev *rcdev,
unsigned long id)+{
- struct reset_simple_data *data = to_reset_simple_data(rcdev);
- int ret;
You could just return -ENOTSUPP here if data->reset_ms == 0.
- ret = reset_simple_assert(rcdev, id);
- if (ret)
return ret;- mdelay(data->reset_ms);
Have you considered specifying the delay in microseconds instead? That would allow to use usleep_range() for shorter delays.
- ret = reset_simple_deassert(rcdev, id);
- if (ret)
return ret;- return 0;
+}
static int reset_simple_status(struct reset_controller_dev *rcdev, unsigned long id) { @@ -80,6 +100,7 @@ static int reset_simple_status(struct reset_controller_dev *rcdev, const struct reset_control_ops reset_simple_ops = { .assert = reset_simple_assert, .deassert = reset_simple_deassert,
- .reset = reset_simple_reset, .status = reset_simple_status,
}; EXPORT_SYMBOL_GPL(reset_simple_ops); diff --git a/include/linux/reset/reset-simple.h b/include/linux/reset/reset-simple.h index 08ccb25a55e6..a5887f6cbe50 100644 --- a/include/linux/reset/reset-simple.h +++ b/include/linux/reset/reset-simple.h @@ -27,6 +27,9 @@
- @status_active_low: if true, bits read back as cleared while the reset is
asserted. Otherwise, bits read back as set while thereset is asserted.
- @reset_ms: Minimum delay in milliseconds needed that needs to be
waited for between an assert and a deassert to reset the
device.
If multiple consumers with different delay requirements are connected to this reset controllers, this must the largest minimum delay. Could you add mention for this in the comment?
regards Philipp