linux-kernel - Re: [PATCH] i2c: qcom-geni: fix I2C frequency table to achieve accurate bus rates

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <y4t3xshxsbrx6xqkxroai3vixjacskco5baaoip2apzjkehjxx@ah6wxu2gy24g>
Date: Wed, 14 May 2025 17:34:24 +0200
From: Andi Shyti <andi.shyti@...nel.org>
To: Kathiravan Thirumoorthy <kathiravan.thirumoorthy@....qualcomm.com>
Cc: Mukesh Kumar Savaliya <quic_msavaliy@...cinc.com>, 
	Viken Dadhaniya <quic_vdadhani@...cinc.com>, Manikanta Mylavarapu <quic_mmanikan@...cinc.com>, 
	Bjorn Andersson <andersson@...nel.org>, linux-i2c@...r.kernel.org, linux-arm-msm@...r.kernel.org, 
	linux-kernel@...r.kernel.org, stable@...nel.org
Subject: Re: [PATCH] i2c: qcom-geni: fix I2C frequency table to achieve
 accurate bus rates

Hi,

On Tue, May 13, 2025 at 04:38:33PM +0530, Kathiravan Thirumoorthy wrote:
> Update the I2C frequency table to match the recommended values
> specified in the I2C hardware programming guide. In the current IPQ5424
> configuration where 32MHz is the source clock, the I2C bus frequencies do
> not meet expectations—for instance, 363KHz is achieved instead of the
> expected 400KHz.
> 
> Cc: stable@...nel.org
> Fixes: 506bb2ab0075 ("i2c: qcom-geni: Support systems with 32MHz serial engine clock")
> Signed-off-by: Kathiravan Thirumoorthy <kathiravan.thirumoorthy@....qualcomm.com>
> ---
>  drivers/i2c/busses/i2c-qcom-geni.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/i2c/busses/i2c-qcom-geni.c b/drivers/i2c/busses/i2c-qcom-geni.c
> index ccea575fb7838db864ca4a2b21ebb3835b2567b2..2fec7b44bfc1baec68e321a9f57de4156120919b 100644
> --- a/drivers/i2c/busses/i2c-qcom-geni.c
> +++ b/drivers/i2c/busses/i2c-qcom-geni.c
> @@ -155,9 +155,9 @@ static const struct geni_i2c_clk_fld geni_i2c_clk_map_19p2mhz[] = {
>  
>  /* source_clock = 32 MHz */
>  static const struct geni_i2c_clk_fld geni_i2c_clk_map_32mhz[] = {
> -	{ I2C_MAX_STANDARD_MODE_FREQ, 8, 14, 18, 40 },
> -	{ I2C_MAX_FAST_MODE_FREQ, 4,  3, 11, 20 },
> -	{ I2C_MAX_FAST_MODE_PLUS_FREQ, 2, 3,  6, 15 },
> +	{ I2C_MAX_STANDARD_MODE_FREQ, 8, 14, 18, 38 },
> +	{ I2C_MAX_FAST_MODE_FREQ, 4,  3, 9, 19 },
> +	{ I2C_MAX_FAST_MODE_PLUS_FREQ, 2, 3, 5, 15 },

argh!

Can someone from Qualcomm look at this fix? Mukesh, Viken?

Thanks,
Andi

>  	{}
>  };
>  
> 
> ---
> base-commit: edef457004774e598fc4c1b7d1d4f0bcd9d0bb30
> change-id: 20250513-i2c-bus-freq-ac46343869a4
> 
> Best regards,
> -- 
> Kathiravan Thirumoorthy <kathiravan.thirumoorthy@....qualcomm.com>
>