Re: [PATCH v11 10/13] usb: dwc3: qcom: Add multiport suspend/resume support for wrapper

From: Konrad Dybcio <konrad.dybcio@linaro.org>
To: Krishna Kurapati <quic_kriskura@quicinc.com>,
	Thinh Nguyen <Thinh.Nguyen@synopsys.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Philipp Zabel <p.zabel@pengutronix.de>,
	Andy Gross <agross@kernel.org>,
	Bjorn Andersson <andersson@kernel.org>,
	Rob Herring <robh+dt@kernel.org>,
	Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
	Felipe Balbi <balbi@kernel.org>,
	Wesley Cheng <quic_wcheng@quicinc.com>,
	Johan Hovold <johan@kernel.org>,
	Mathias Nyman <mathias.nyman@intel.com>
Cc: linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-arm-msm@vger.kernel.org, devicetree@vger.kernel.org,
	quic_pkondeti@quicinc.com, quic_ppratap@quicinc.com,
	quic_jackp@quicinc.com, ahalaney@redhat.com,
	quic_shazhuss@quicinc.com
Subject: Re: [PATCH v11 10/13] usb: dwc3: qcom: Add multiport suspend/resume support for wrapper
Date: Fri, 15 Sep 2023 15:48:21 +0200	[thread overview]
Message-ID: <825bc60b-2067-43e2-8b43-9d38b7cebf02@linaro.org> (raw)
In-Reply-To: <20230828133033.11988-11-quic_kriskura@quicinc.com>

On 28.08.2023 15:30, Krishna Kurapati wrote:
> QCOM SoC SA8295P's tertiary quad port controller supports 2 HS+SS
> ports and 2 HS only ports. Add support for configuring PWR_EVENT_IRQ's
> for all the ports during suspend/resume.
> 
> Signed-off-by: Krishna Kurapati <quic_kriskura@quicinc.com>
> ---
>  drivers/usb/dwc3/dwc3-qcom.c | 39 +++++++++++++++++++++++++++++-------
>  1 file changed, 32 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/usb/dwc3/dwc3-qcom.c b/drivers/usb/dwc3/dwc3-qcom.c
> index f8f8c5e39a01..34eeebb74a6a 100644
> --- a/drivers/usb/dwc3/dwc3-qcom.c
> +++ b/drivers/usb/dwc3/dwc3-qcom.c
> @@ -37,7 +37,11 @@
>  #define PIPE3_PHYSTATUS_SW			BIT(3)
>  #define PIPE_UTMI_CLK_DIS			BIT(8)
>  
> -#define PWR_EVNT_IRQ_STAT_REG			0x58
> +#define PWR_EVNT_IRQ1_STAT_REG			0x58
> +#define PWR_EVNT_IRQ2_STAT_REG			0x1dc
> +#define PWR_EVNT_IRQ3_STAT_REG			0x228
> +#define PWR_EVNT_IRQ4_STAT_REG			0x238
> +
>  #define PWR_EVNT_LPM_IN_L2_MASK			BIT(4)
>  #define PWR_EVNT_LPM_OUT_L2_MASK		BIT(5)
>  
> @@ -107,6 +111,19 @@ struct dwc3_qcom {
>  	int			num_ports;
>  };
>  
> +/*
> + * SA8295 has 4 power event IRQ STAT registers to be checked
> + * during suspend resume.
> + */
But this driver supports much more than just SA8295?

> +#define NUM_PWR_EVENT_STAT_REGS	4
> +
> +static u32 pwr_evnt_irq_stat_reg_offset[NUM_PWR_EVENT_STAT_REGS] = {
> +	PWR_EVNT_IRQ1_STAT_REG,
> +	PWR_EVNT_IRQ2_STAT_REG,
> +	PWR_EVNT_IRQ3_STAT_REG,
> +	PWR_EVNT_IRQ4_STAT_REG,
> +};
> +
>  static inline void dwc3_qcom_setbits(void __iomem *base, u32 offset, u32 val)
>  {
>  	u32 reg;
> @@ -440,15 +457,19 @@ static void dwc3_qcom_enable_interrupts(struct dwc3_qcom *qcom)
>  
>  static int dwc3_qcom_suspend(struct dwc3_qcom *qcom, bool wakeup)
>  {
> +	u8 num_ports;
Maybe I'm picky, but I'm not sure defining a variable for
a single use of an object with a rather short name
(qcom->num_ports) is justified, here and below..

Konrad