linux-kernel - Re: [PATCH v2 3/6] usb: typec: tcpci_rt1711h: Add regulator support when source vbus

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]

Date:   Thu, 21 Jul 2022 07:28:36 -0700
From:   Guenter Roeck <linux@...ck-us.net>
To:     Gene Chen <gene.chen.richtek@...il.com>,
        heikki.krogerus@...ux.intel.com, gregkh@...uxfoundation.org,
        robh+dt@...nel.org, krzysztof.kozlowski+dt@...aro.org
Cc:     linux-usb@...r.kernel.org, linux-kernel@...r.kernel.org,
        devicetree@...r.kernel.org, gene_chen@...htek.com,
        cy_huang@...htek.com
Subject: Re: [PATCH v2 3/6] usb: typec: tcpci_rt1711h: Add regulator support
 when source vbus

On 7/20/22 23:11, Gene Chen wrote:
> From: Gene Chen <gene_chen@...htek.com>
> 
> Add regulator support when source vbus
> 
> Signed-off-by: Gene Chen <gene_chen@...htek.com>
> ---
>   drivers/usb/typec/tcpm/tcpci_rt1711h.c | 28 ++++++++++++++++++++++++++
>   1 file changed, 28 insertions(+)
> 
> diff --git a/drivers/usb/typec/tcpm/tcpci_rt1711h.c b/drivers/usb/typec/tcpm/tcpci_rt1711h.c
> index 3309ceace2b2..52c9594e531d 100644
> --- a/drivers/usb/typec/tcpm/tcpci_rt1711h.c
> +++ b/drivers/usb/typec/tcpm/tcpci_rt1711h.c
> @@ -10,6 +10,7 @@
>   #include <linux/i2c.h>
>   #include <linux/interrupt.h>
>   #include <linux/gpio/consumer.h>
> +#include <linux/regulator/consumer.h>
>   #include <linux/usb/tcpm.h>
>   #include <linux/regmap.h>
>   #include "tcpci.h"
> @@ -40,6 +41,8 @@ struct rt1711h_chip {
>   	struct tcpci_data data;
>   	struct tcpci *tcpci;
>   	struct device *dev;
> +	struct regulator *vbus;
> +	bool src_en;
>   };
>   
>   static int rt1711h_read16(struct rt1711h_chip *chip, unsigned int reg, u16 *val)
> @@ -103,6 +106,26 @@ static int rt1711h_init(struct tcpci *tcpci, struct tcpci_data *tdata)
>   
>   	/* dcSRC.DRP : 33% */
>   	return rt1711h_write16(chip, RT1711H_RTCTRL16, 330);
> +
> +}
> +
> +static int rt1711h_set_vbus(struct tcpci *tcpci, struct tcpci_data *tdata,
> +			    bool src, bool snk)
> +{
> +	struct rt1711h_chip *chip = tdata_to_rt1711h(tdata);
> +	int ret;
> +
> +	if (chip->src_en == src)
> +		return 1;
> +
> +	if (src)
> +		ret = regulator_enable(chip->vbus);
> +	else
> +		ret = regulator_disable(chip->vbus);
> +
> +	if (!ret)
> +		chip->src_en = src;
> +	return ret ? ret : 1;

Are you sure this is what you want ? Returning 1 bypasses the code setting
the vbus registers in tcpci.c. If that is on purpose it might make sense
to explain it.

>   }
>   
>   static int rt1711h_set_vconn(struct tcpci *tcpci, struct tcpci_data *tdata,
> @@ -246,7 +269,12 @@ static int rt1711h_probe(struct i2c_client *client,
>   	if (ret < 0)
>   		return ret;
>   
> +	chip->vbus = devm_regulator_get(&client->dev, "vbus");
> +	if (IS_ERR(chip->vbus))
> +		return PTR_ERR(chip->vbus);
> +

This makes regulator support mandatory, which so far was not the case.
That warrants an explanation why it is not a problem for existing users.

Thanks,
Guenter

>   	chip->data.init = rt1711h_init;
> +	chip->data.set_vbus = rt1711h_set_vbus;
>   	chip->data.set_vconn = rt1711h_set_vconn;
>   	chip->data.start_drp_toggling = rt1711h_start_drp_toggling;
>   	chip->tcpci = tcpci_register_port(chip->dev, &chip->data);