Re: [PATCH V3 4/8] i2c: i2c-qcom-geni: Add interconnect support

From: Matthias Kaehlcke <mka@chromium.org>
To: Akash Asthana <akashast@codeaurora.org>
Cc: gregkh@linuxfoundation.org, agross@kernel.org,
	bjorn.andersson@linaro.org, wsa@the-dreams.de,
	broonie@kernel.org, mark.rutland@arm.com, robh+dt@kernel.org,
	georgi.djakov@linaro.org, linux-i2c@vger.kernel.org,
	linux-spi@vger.kernel.org, devicetree@vger.kernel.org,
	swboyd@chromium.org, mgautam@codeaurora.org,
	linux-arm-msm@vger.kernel.org, linux-serial@vger.kernel.org,
	dianders@chromium.org, evgreen@chromium.org
Subject: Re: [PATCH V3 4/8] i2c: i2c-qcom-geni: Add interconnect support
Date: Tue, 31 Mar 2020 11:49:39 -0700	[thread overview]
Message-ID: <20200331184939.GI199755@google.com> (raw)
In-Reply-To: <1585652976-17481-5-git-send-email-akashast@codeaurora.org>

Hi Akash,

On Tue, Mar 31, 2020 at 04:39:32PM +0530, Akash Asthana wrote:
> Get the interconnect paths for I2C based Serial Engine device
> and vote according to the bus speed of the driver.
> 
> Signed-off-by: Akash Asthana <akashast@codeaurora.org>
> ---
> Changes in V2:
>  - As per Bjorn's comment, removed se == NULL check from geni_i2c_icc_get
>  - As per Bjorn's comment, removed code to set se->icc_path* to NULL in failure
>  - As per Bjorn's comment, introduced and using devm_of_icc_get API for getting
>    path handle
>  - As per Matthias comment, added error handling for icc_set_bw call
> 
> Changes in V3:
>  - As per Matthias comment, use common library APIs defined in geni-se
>    driver for ICC functionality.
> 
>  drivers/i2c/busses/i2c-qcom-geni.c | 30 +++++++++++++++++++++++++++++-
>  1 file changed, 29 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/i2c/busses/i2c-qcom-geni.c b/drivers/i2c/busses/i2c-qcom-geni.c
> index 18d1e4f..373c2ca 100644
> --- a/drivers/i2c/busses/i2c-qcom-geni.c
> +++ b/drivers/i2c/busses/i2c-qcom-geni.c
> @@ -557,6 +557,26 @@ static int geni_i2c_probe(struct platform_device *pdev)
>  	gi2c->adap.dev.of_node = dev->of_node;
>  	strlcpy(gi2c->adap.name, "Geni-I2C", sizeof(gi2c->adap.name));
>  
> +	ret = geni_icc_get(&gi2c->se, "qup-core", "qup-config", "qup-memory");
> +	if (ret)
> +		return ret;
> +	/*
> +	 * Set the bus quota for core and cpu to a reasonable value for
> +	 * register access.
> +	 * Set quota for DDR based on bus speed, assume peak requirement
> +	 * as twice of avg bw.
> +	 */
> +	gi2c->se.to_core.avg_bw = GENI_DEFAULT_BW;
> +	gi2c->se.to_core.peak_bw = Bps_to_icc(CORE_2X_100_MHZ);
> +	gi2c->se.from_cpu.avg_bw = GENI_DEFAULT_BW;
> +	gi2c->se.from_cpu.peak_bw = GENI_DEFAULT_BW;
> +	gi2c->se.to_ddr.avg_bw = Bps_to_icc(gi2c->clk_freq_out);
> +	gi2c->se.to_ddr.peak_bw = Bps_to_icc(2 * gi2c->clk_freq_out);
> +
> +	ret = geni_icc_vote_on(&gi2c->se);
> +	if (ret)
> +		return ret;
> +
>  	ret = geni_se_resources_on(&gi2c->se);
>  	if (ret) {
>  		dev_err(dev, "Error turning on resources %d\n", ret);

I think you need to call geni_icc_vote_off() here and in other error paths.