lkml.org 
[lkml]   [2022]   [Apr]   [7]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
SubjectRe: [PATCH] tpm: cr50: Add new device/vendor ID 0x504a6666
From
Dear Jes,


Thank you for your patch.

Am 05.04.22 um 19:37 schrieb Jes B. Klinke:
> Accept one additional numerical value of DID:VID for next generation
> Google TPM, to be used in future Chromebooks.

Maybe extend:

… Google TPM with new firmware …

The TPM with the new firmware has the code name TI50, and going to use
the same interfaces.

> This patch touches more lines than may seem necessary, as a result of
> the need to move the error case to sit after the two recognized cases.
>
> Signed-off-by: Jes B. Klinke <jbk@chromium.org>
> ---
>
> drivers/char/tpm/tpm_tis_i2c_cr50.c | 21 +++++++++++++--------
> 1 file changed, 13 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/char/tpm/tpm_tis_i2c_cr50.c b/drivers/char/tpm/tpm_tis_i2c_cr50.c
> index f6c0affbb4567..bf54ebd6724b0 100644
> --- a/drivers/char/tpm/tpm_tis_i2c_cr50.c
> +++ b/drivers/char/tpm/tpm_tis_i2c_cr50.c
> @@ -31,6 +31,7 @@
> #define TPM_CR50_TIMEOUT_SHORT_MS 2 /* Short timeout during transactions */
> #define TPM_CR50_TIMEOUT_NOIRQ_MS 20 /* Timeout for TPM ready without IRQ */
> #define TPM_CR50_I2C_DID_VID 0x00281ae0L /* Device and vendor ID reg value */
> +#define TPM_TI50_I2C_DID_VID 0x504a6666L /* Device and vendor ID reg value */
> #define TPM_CR50_I2C_MAX_RETRIES 3 /* Max retries due to I2C errors */
> #define TPM_CR50_I2C_RETRY_DELAY_LO 55 /* Min usecs between retries on I2C */
> #define TPM_CR50_I2C_RETRY_DELAY_HI 65 /* Max usecs between retries on I2C */
> @@ -742,16 +743,20 @@ static int tpm_cr50_i2c_probe(struct i2c_client *client)
> }
>
> vendor = le32_to_cpup((__le32 *)buf);
> - if (vendor != TPM_CR50_I2C_DID_VID) {
> - dev_err(dev, "Vendor ID did not match! ID was %08x\n", vendor);
> - tpm_cr50_release_locality(chip, true);
> - return -ENODEV;
> + if (vendor == TPM_CR50_I2C_DID_VID) {
> + dev_info(dev, "cr50 TPM 2.0 (i2c 0x%02x irq %d id 0x%x)\n",
> + client->addr, client->irq, vendor >> 16);
> + return tpm_chip_register(chip);
> + }
> + if (vendor == TPM_TI50_I2C_DID_VID) {
> + dev_info(dev, "ti50 TPM 2.0 (i2c 0x%02x irq %d id 0x%x)\n",
> + client->addr, client->irq, vendor >> 16);
> + return tpm_chip_register(chip);
> }

Both branches are quite similar. Can a ternary operator be used?

dev_info(dev, "%s TPM 2.0 (i2c 0x%02x irq %d id 0x%x)\n",
(vendor == TPM_CR50_I2C_DID_VID) ? "cr50" : "ti50", client->addr,
client->irq, vendor >> 16);
return tpm_chip_register(chip);

and the original flow be left? (A separate variable can also be added.)

>
> - dev_info(dev, "cr50 TPM 2.0 (i2c 0x%02x irq %d id 0x%x)\n",
> - client->addr, client->irq, vendor >> 16);
> -
> - return tpm_chip_register(chip);
> + dev_err(dev, "Vendor ID did not match! ID was %08x\n", vendor);
> + tpm_cr50_release_locality(chip, true);
> + return -ENODEV;
> }
>
> /**


Kind regards,

Paul

\
 
 \ /
  Last update: 2022-04-07 17:31    [W:0.277 / U:0.084 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site