2020-08-28 13:21:38

by Heikki Krogerus

[permalink] [raw]
Subject: Re: [PATCH 02/14 v2] usb: typec: tcpci: Add support when hidden tx registers are inaccessible

Looks like you forgot v1 somewhere :-)

On Mon, Aug 24, 2020 at 09:21:58PM -0700, Badhri Jagan Sridharan wrote:
> TCPCI spec forbids direct access of TX_BUF_BYTE_x register.
> The existing version of tcpci driver assumes that those registers
> are directly addressible. Add support for tcpci chips which do
> not support direct access to TX_BUF_BYTE_x registers. TX_BUF_BYTE_x
> can only be accessed by I2C_WRITE_BYTE_COUNT.
>
> Signed-off-by: Badhri Jagan Sridharan <[email protected]>
> ---
> drivers/usb/typec/tcpm/tcpci.c | 49 +++++++++++++++++++++++++---------
> drivers/usb/typec/tcpm/tcpci.h | 8 ++++++
> 2 files changed, 44 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/usb/typec/tcpm/tcpci.c b/drivers/usb/typec/tcpm/tcpci.c
> index f57d91fd0e09..90d348caa6a8 100644
> --- a/drivers/usb/typec/tcpm/tcpci.c
> +++ b/drivers/usb/typec/tcpm/tcpci.c
> @@ -320,8 +320,7 @@ static int tcpci_set_vbus(struct tcpc_dev *tcpc, bool source, bool sink)
> return 0;
> }
>
> -static int tcpci_pd_transmit(struct tcpc_dev *tcpc,
> - enum tcpm_transmit_type type,
> +static int tcpci_pd_transmit(struct tcpc_dev *tcpc, enum tcpm_transmit_type type,
> const struct pd_message *msg)

That does not look like a relevant change.

> {
> struct tcpci *tcpci = tcpc_to_tcpci(tcpc);
> @@ -330,23 +329,47 @@ static int tcpci_pd_transmit(struct tcpc_dev *tcpc,
> int ret;
>
> cnt = msg ? pd_header_cnt(header) * 4 : 0;
> - ret = regmap_write(tcpci->regmap, TCPC_TX_BYTE_CNT, cnt + 2);
> - if (ret < 0)
> - return ret;
> + /**
> + * TCPCI spec forbids direct access of TCPC_TX_DATA.
> + * But, since some of the chipsets offer this capability,
> + * it's fair to support both.
> + */
> + if (!tcpci->data->TX_BUF_BYTE_x_hidden) {

Couldn't check if the flag is set first?

if (tcpci->data->TX_BUF_BYTE_x_hidden) {
...

> + ret = regmap_write(tcpci->regmap, TCPC_TX_BYTE_CNT, cnt + 2);
> + if (ret < 0)
> + return ret;
>
> - ret = tcpci_write16(tcpci, TCPC_TX_HDR, header);
> - if (ret < 0)
> - return ret;
> + ret = tcpci_write16(tcpci, TCPC_TX_HDR, header);
> + if (ret < 0)
> + return ret;
> +
> + if (cnt > 0) {
> + ret = regmap_raw_write(tcpci->regmap, TCPC_TX_DATA, &msg->payload, cnt);
> + if (ret < 0)
> + return ret;
> + }
> + } else {
> + u8 buf[TCPC_TRANSMIT_BUFFER_MAX_LEN] = {0,};
> + u8 pos = 0;
> +
> + /* Payload + header + TCPC_TX_BYTE_CNT */
> + buf[pos++] = cnt + 2;
> +
> + if (msg)
> + memcpy(&buf[pos], &msg->header, sizeof(msg->header));
> +
> + pos += sizeof(header);
> +
> + if (cnt > 0)
> + memcpy(&buf[pos], msg->payload, cnt);
>
> - if (cnt > 0) {
> - ret = regmap_raw_write(tcpci->regmap, TCPC_TX_DATA,
> - &msg->payload, cnt);
> + pos += cnt;
> + ret = regmap_raw_write(tcpci->regmap, TCPC_TX_BYTE_CNT, buf, pos);
> if (ret < 0)
> return ret;
> }
>
> - reg = (PD_RETRY_COUNT << TCPC_TRANSMIT_RETRY_SHIFT) |
> - (type << TCPC_TRANSMIT_TYPE_SHIFT);
> + reg = (PD_RETRY_COUNT << TCPC_TRANSMIT_RETRY_SHIFT) | (type << TCPC_TRANSMIT_TYPE_SHIFT);
> ret = regmap_write(tcpci->regmap, TCPC_TRANSMIT, reg);
> if (ret < 0)
> return ret;
> diff --git a/drivers/usb/typec/tcpm/tcpci.h b/drivers/usb/typec/tcpm/tcpci.h
> index fd26ca35814c..cf9d8b63adcb 100644
> --- a/drivers/usb/typec/tcpm/tcpci.h
> +++ b/drivers/usb/typec/tcpm/tcpci.h
> @@ -128,9 +128,17 @@
> #define TCPC_VBUS_VOLTAGE_ALARM_HI_CFG 0x76
> #define TCPC_VBUS_VOLTAGE_ALARM_LO_CFG 0x78
>
> +/* I2C_WRITE_BYTE_COUNT + 1 when TX_BUF_BYTE_x is only accessible I2C_WRITE_BYTE_COUNT */
> +#define TCPC_TRANSMIT_BUFFER_MAX_LEN 31
> +
> +/*
> + * @TX_BUF_BYTE_x_hidden
> + * optional; Set when TX_BUF_BYTE_x can only be accessed through I2C_WRITE_BYTE_COUNT.
> + */
> struct tcpci;
> struct tcpci_data {
> struct regmap *regmap;
> + unsigned char TX_BUF_BYTE_x_hidden:1;
> int (*init)(struct tcpci *tcpci, struct tcpci_data *data);
> int (*set_vconn)(struct tcpci *tcpci, struct tcpci_data *data,
> bool enable);
> --
> 2.28.0.297.g1956fa8f8d-goog

thanks,

--
heikki


2020-08-28 14:51:13

by Badhri Jagan Sridharan

[permalink] [raw]
Subject: Re: [PATCH 02/14 v2] usb: typec: tcpci: Add support when hidden tx registers are inaccessible

On Fri, Aug 28, 2020 at 6:12 AM Heikki Krogerus
<[email protected]> wrote:
>
> Looks like you forgot v1 somewhere :-)


Dumb me :P Yeah I was doing the patch numbers manually causing the confusion.
Greg was complaining as well.
These are all v1. I will re-upload everything as v2. Just noticed that
I can use the -v option.

>
>
> On Mon, Aug 24, 2020 at 09:21:58PM -0700, Badhri Jagan Sridharan wrote:
> > TCPCI spec forbids direct access of TX_BUF_BYTE_x register.
> > The existing version of tcpci driver assumes that those registers
> > are directly addressible. Add support for tcpci chips which do
> > not support direct access to TX_BUF_BYTE_x registers. TX_BUF_BYTE_x
> > can only be accessed by I2C_WRITE_BYTE_COUNT.
> >
> > Signed-off-by: Badhri Jagan Sridharan <[email protected]>
> > ---
> > drivers/usb/typec/tcpm/tcpci.c | 49 +++++++++++++++++++++++++---------
> > drivers/usb/typec/tcpm/tcpci.h | 8 ++++++
> > 2 files changed, 44 insertions(+), 13 deletions(-)
> >
> > diff --git a/drivers/usb/typec/tcpm/tcpci.c b/drivers/usb/typec/tcpm/tcpci.c
> > index f57d91fd0e09..90d348caa6a8 100644
> > --- a/drivers/usb/typec/tcpm/tcpci.c
> > +++ b/drivers/usb/typec/tcpm/tcpci.c
> > @@ -320,8 +320,7 @@ static int tcpci_set_vbus(struct tcpc_dev *tcpc, bool source, bool sink)
> > return 0;
> > }
> >
> > -static int tcpci_pd_transmit(struct tcpc_dev *tcpc,
> > - enum tcpm_transmit_type type,
> > +static int tcpci_pd_transmit(struct tcpc_dev *tcpc, enum tcpm_transmit_type type,
> > const struct pd_message *msg)
>
> That does not look like a relevant change.
>
> > {
> > struct tcpci *tcpci = tcpc_to_tcpci(tcpc);
> > @@ -330,23 +329,47 @@ static int tcpci_pd_transmit(struct tcpc_dev *tcpc,
> > int ret;
> >
> > cnt = msg ? pd_header_cnt(header) * 4 : 0;
> > - ret = regmap_write(tcpci->regmap, TCPC_TX_BYTE_CNT, cnt + 2);
> > - if (ret < 0)
> > - return ret;
> > + /**
> > + * TCPCI spec forbids direct access of TCPC_TX_DATA.
> > + * But, since some of the chipsets offer this capability,
> > + * it's fair to support both.
> > + */
> > + if (!tcpci->data->TX_BUF_BYTE_x_hidden) {
>
> Couldn't check if the flag is set first?

Yes will do !

>
> if (tcpci->data->TX_BUF_BYTE_x_hidden) {
> ...
>
> > + ret = regmap_write(tcpci->regmap, TCPC_TX_BYTE_CNT, cnt + 2);
> > + if (ret < 0)
> > + return ret;
> >
> > - ret = tcpci_write16(tcpci, TCPC_TX_HDR, header);
> > - if (ret < 0)
> > - return ret;
> > + ret = tcpci_write16(tcpci, TCPC_TX_HDR, header);
> > + if (ret < 0)
> > + return ret;
> > +
> > + if (cnt > 0) {
> > + ret = regmap_raw_write(tcpci->regmap, TCPC_TX_DATA, &msg->payload, cnt);
> > + if (ret < 0)
> > + return ret;
> > + }
> > + } else {
> > + u8 buf[TCPC_TRANSMIT_BUFFER_MAX_LEN] = {0,};
> > + u8 pos = 0;
> > +
> > + /* Payload + header + TCPC_TX_BYTE_CNT */
> > + buf[pos++] = cnt + 2;
> > +
> > + if (msg)
> > + memcpy(&buf[pos], &msg->header, sizeof(msg->header));
> > +
> > + pos += sizeof(header);
> > +
> > + if (cnt > 0)
> > + memcpy(&buf[pos], msg->payload, cnt);
> >
> > - if (cnt > 0) {
> > - ret = regmap_raw_write(tcpci->regmap, TCPC_TX_DATA,
> > - &msg->payload, cnt);
> > + pos += cnt;
> > + ret = regmap_raw_write(tcpci->regmap, TCPC_TX_BYTE_CNT, buf, pos);
> > if (ret < 0)
> > return ret;
> > }
> >
> > - reg = (PD_RETRY_COUNT << TCPC_TRANSMIT_RETRY_SHIFT) |
> > - (type << TCPC_TRANSMIT_TYPE_SHIFT);
> > + reg = (PD_RETRY_COUNT << TCPC_TRANSMIT_RETRY_SHIFT) | (type << TCPC_TRANSMIT_TYPE_SHIFT);
> > ret = regmap_write(tcpci->regmap, TCPC_TRANSMIT, reg);
> > if (ret < 0)
> > return ret;
> > diff --git a/drivers/usb/typec/tcpm/tcpci.h b/drivers/usb/typec/tcpm/tcpci.h
> > index fd26ca35814c..cf9d8b63adcb 100644
> > --- a/drivers/usb/typec/tcpm/tcpci.h
> > +++ b/drivers/usb/typec/tcpm/tcpci.h
> > @@ -128,9 +128,17 @@
> > #define TCPC_VBUS_VOLTAGE_ALARM_HI_CFG 0x76
> > #define TCPC_VBUS_VOLTAGE_ALARM_LO_CFG 0x78
> >
> > +/* I2C_WRITE_BYTE_COUNT + 1 when TX_BUF_BYTE_x is only accessible I2C_WRITE_BYTE_COUNT */
> > +#define TCPC_TRANSMIT_BUFFER_MAX_LEN 31
> > +
> > +/*
> > + * @TX_BUF_BYTE_x_hidden
> > + * optional; Set when TX_BUF_BYTE_x can only be accessed through I2C_WRITE_BYTE_COUNT.
> > + */
> > struct tcpci;
> > struct tcpci_data {
> > struct regmap *regmap;
> > + unsigned char TX_BUF_BYTE_x_hidden:1;
> > int (*init)(struct tcpci *tcpci, struct tcpci_data *data);
> > int (*set_vconn)(struct tcpci *tcpci, struct tcpci_data *data,
> > bool enable);
> > --
> > 2.28.0.297.g1956fa8f8d-goog
>
> thanks,
>
> --
> heikki