Re: [PATCH] tpm_tis_spi: set default probe function if device id not match

From: 乱石
Date: Sun May 09 2021 - 21:24:30 EST


在 2021/5/10 4:39, Jarkko Sakkinen 写道:
On Sat, May 08, 2021 at 10:46:57AM +0800, 乱石 wrote:
Hi,

在 2021/5/8 10:01, Jarkko Sakkinen 写道:
On Fri, May 07, 2021 at 10:52:55PM +0800, Liguang Zhang wrote:
In DSDT table, TPM _CID was SMO0768, and no _HID definition. After a
kernel upgrade from 4.19 to 5.10, TPM probe function was changed which
causes device probe fails. In order to make newer kernel to be
compatible with the older acpi definition, it would be best set default
probe function.

Signed-off-by: Liguang Zhang <zhangliguang@xxxxxxxxxxxxxxxxx>
---
drivers/char/tpm/tpm_tis_spi_main.c | 12 ++++++++----
1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/drivers/char/tpm/tpm_tis_spi_main.c b/drivers/char/tpm/tpm_tis_spi_main.c
index 3856f6ebcb34..da632a582621 100644
--- a/drivers/char/tpm/tpm_tis_spi_main.c
+++ b/drivers/char/tpm/tpm_tis_spi_main.c
@@ -240,10 +240,14 @@ static int tpm_tis_spi_driver_probe(struct spi_device *spi)
tpm_tis_spi_probe_func probe_func;
probe_func = of_device_get_match_data(&spi->dev);
- if (!probe_func && spi_dev_id)
- probe_func = (tpm_tis_spi_probe_func)spi_dev_id->driver_data;
- if (!probe_func)
- return -ENODEV;
+ if (!probe_func) {
+ if (spi_dev_id) {
+ probe_func = (tpm_tis_spi_probe_func)spi_dev_id->driver_data;
+ if (!probe_func)
+ return -ENODEV;
Perhaps also hear fallback to tpm_tis_spi_probe?

Yes, I do not think of a good way. Do you have any suggestions?
So, I just think that when you have this part:


if (!probe_func) {
if (spi_dev_id) {
probe_func = (tpm_tis_spi_probe_func)spi_dev_id->driver_data;
if (!probe_func)
return -ENODEV;

Why in here would not you also want to fallback to tpm_tis_spi_probe?

Thanks, I got it. If spi_dev_id exists, prob_func is NULL, I think it's not reasonable , but not neccessarily correct.

In this scenario, maybe can also fallback to tpm_tis_spi_probe.


Liguang


/Jarkko