RE: [PATCH] staging: typec: handle vendor defined part and modify drp toggling flow

From: Jun Li
Date: Thu Feb 22 2018 - 05:16:25 EST

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Hi,

> -----Original Message-----
> From: linux-usb-owner@xxxxxxxxxxxxxxx
> [mailto:linux-usb-owner@xxxxxxxxxxxxxxx] On Behalf Of ShuFanLee
> Sent: 2018年2月21日 23:02
> To: heikki.krogerus@xxxxxxxxxxxxxxx; linux@xxxxxxxxxxxx; greg@xxxxxxxxx
> Cc: shufan_lee@xxxxxxxxxxx; cy_huang@xxxxxxxxxxx;
> linux-kernel@xxxxxxxxxxxxxxx; linux-usb@xxxxxxxxxxxxxxx
> Subject: [PATCH] staging: typec: handle vendor defined part and modify drp
> toggling flow
>
> From: ShuFanLee <shufan_lee@xxxxxxxxxxx>
>
> Handle vendor defined behavior in tcpci_init, tcpci_set_vconn and export
> tcpci_irq.
> More operations can be extended in tcpci_data if needed.
> According to TCPCI specification, 4.4.5.2 ROLE_CONTROL, TCPC shall not
> start DRP toggling until subsequently the TCPM writes to the COMMAND
> register to start DRP toggling.

My understanding of above statement is TCPM(this Linux driver) can enable
DRP and CC1/CC2 in one shot, but TCPC(your typec chip internal firmware)
needs wait until TCPM writes to COMMAND register to start drp toggling.

> DRP toggling flow is chagned as following:
> - Write DRP = 0 & Rd/Rd

Why fixed to be Rd/Rd? in this case, it means the starting value:

Tcpci 4.4.5.2:
"When initiating autonomous DRP toggling, the TCPM shall write B6 (DRP) =1b
and the starting value of Rp/Rd to B3..0 (CC1/CC2) to indicate DRP autonomous
toggling mode to the TCPC."

> - Write DRP = 1

What's your problem if combine above 2 in one shot?

> - Set LOOK4CONNECTION command
>
> Signed-off-by: ShuFanLee <shufan_lee@xxxxxxxxxxx>
> ---
> drivers/staging/typec/tcpci.c | 128
> +++++++++++++++++++++++++++++++++---------
> drivers/staging/typec/tcpci.h | 13 +++++
> 2 files changed, 115 insertions(+), 26 deletions(-)
>
> patch changelogs between v1 & v2
> - Remove unnecessary i2c_client in the structure of tcpci
> - Rename structure of tcpci_vendor_data to tcpci_data
> - Not exporting tcpci read/write wrappers but register i2c regmap in glue
> driver
> - Add set_vconn ops in tcpci_data
> (It is necessary for RT1711H to enable/disable idle mode before
> disabling/enabling vconn)
> - Export tcpci_irq so that vendor can call it in their own IRQ handler
>
> patch changelogs between v2 & v3
> - Change the return type of tcpci_irq from int to irqreturn_t
>
> diff --git a/drivers/staging/typec/tcpci.c b/drivers/staging/typec/tcpci.c
> index 9bd4412..4959c69 100644
> --- a/drivers/staging/typec/tcpci.c
> +++ b/drivers/staging/typec/tcpci.c
> @@ -21,7 +21,6 @@
>
> struct tcpci {
> struct device *dev;
> - struct i2c_client *client;
>
> struct tcpm_port *port;
>
> @@ -30,6 +29,12 @@ struct tcpci {
> bool controls_vbus;
>
> struct tcpc_dev tcpc;
> + struct tcpci_data *data;
> +};
> +
> +struct tcpci_chip {
> + struct tcpci *tcpci;
> + struct tcpci_data data;
> };
>
> static inline struct tcpci *tcpc_to_tcpci(struct tcpc_dev *tcpc) @@ -37,8
> +42,7 @@ static inline struct tcpci *tcpc_to_tcpci(struct tcpc_dev *tcpc)
> return container_of(tcpc, struct tcpci, tcpc); }
>
> -static int tcpci_read16(struct tcpci *tcpci, unsigned int reg,
> - u16 *val)
> +static int tcpci_read16(struct tcpci *tcpci, unsigned int reg, u16
> +*val)
> {
> return regmap_raw_read(tcpci->regmap, reg, val, sizeof(u16)); } @@
> -98,8 +102,10 @@ static int tcpci_set_cc(struct tcpc_dev *tcpc, enum
> typec_cc_status cc) static int tcpci_start_drp_toggling(struct tcpc_dev
> *tcpc,
> enum typec_cc_status cc)
> {
> + int ret;
> struct tcpci *tcpci = tcpc_to_tcpci(tcpc);
> - unsigned int reg = TCPC_ROLE_CTRL_DRP;
> + unsigned int reg = (TCPC_ROLE_CTRL_CC_RD <<
> TCPC_ROLE_CTRL_CC1_SHIFT) |
> + (TCPC_ROLE_CTRL_CC_RD <<
> TCPC_ROLE_CTRL_CC2_SHIFT);
>
> switch (cc) {
> default:
> @@ -117,7 +123,19 @@ static int tcpci_start_drp_toggling(struct tcpc_dev
> *tcpc,
> break;
> }
>
> - return regmap_write(tcpci->regmap, TCPC_ROLE_CTRL, reg);
> + ret = regmap_write(tcpci->regmap, TCPC_ROLE_CTRL, reg);
> + if (ret < 0)
> + return ret;
> + usleep_range(500, 1000);

Why need a wait here? It seems you actually don't want to do autonomously toggling
from the very beginning, instead, you begin with a directly control on CC, keep it(Rd)
for some time, then switch to use autonomously toggling, why you need such kind of
sequence? I think it's special and not following tcpci spec.

> + reg |= TCPC_ROLE_CTRL_DRP;
> + ret = regmap_write(tcpci->regmap, TCPC_ROLE_CTRL, reg);
> + if (ret < 0)
> + return ret;
> + ret = regmap_write(tcpci->regmap, TCPC_COMMAND,
> + TCPC_CMD_LOOK4CONNECTION);
> + if (ret < 0)
> + return ret;
> + return 0;
> }
>
> static enum typec_cc_status tcpci_to_typec_cc(unsigned int cc, bool sink)
> @@ -178,6 +196,16 @@ static int tcpci_set_vconn(struct tcpc_dev *tcpc,
> bool enable)
> struct tcpci *tcpci = tcpc_to_tcpci(tcpc);
> int ret;
>
> + /* Handle vendor set vconn */
> + if (tcpci->data) {
> + if (tcpci->data->set_vconn) {
> + ret = tcpci->data->set_vconn(tcpci, tcpci->data,
> + enable);
> + if (ret < 0)
> + return ret;
> + }
> + }
> +
> ret = regmap_write(tcpci->regmap, TCPC_POWER_CTRL,
> enable ? TCPC_POWER_CTRL_VCONN_ENABLE : 0);
> if (ret < 0)
> @@ -323,6 +351,15 @@ static int tcpci_init(struct tcpc_dev *tcpc)
> if (time_after(jiffies, timeout))
> return -ETIMEDOUT;
>
> + /* Handle vendor init */
> + if (tcpci->data) {
> + if (tcpci->data->init) {
> + ret = tcpci->data->init(tcpci, tcpci->data);
> + if (ret < 0)
> + return ret;
> + }
> + }
> +
> /* Clear all events */
> ret = tcpci_write16(tcpci, TCPC_ALERT, 0xffff);
> if (ret < 0)
> @@ -344,9 +381,15 @@ static int tcpci_init(struct tcpc_dev *tcpc)
> return tcpci_write16(tcpci, TCPC_ALERT_MASK, reg); }
>
> -static irqreturn_t tcpci_irq(int irq, void *dev_id)
> +static irqreturn_t _tcpci_irq(int irq, void *dev_id)
> {
> struct tcpci *tcpci = dev_id;
> +
> + return tcpci_irq(tcpci);
> +}
> +
> +irqreturn_t tcpci_irq(struct tcpci *tcpci) {
> u16 status;
>
> tcpci_read16(tcpci, TCPC_ALERT, &status); @@ -412,6 +455,7 @@
> static irqreturn_t tcpci_irq(int irq, void *dev_id)
>
> return IRQ_HANDLED;
> }
> +EXPORT_SYMBOL_GPL(tcpci_irq);

I don't catch the point of how you handle private events by above change,
maybe post your RT1711H part as a user in one series can make it clear,
I assume this can be done in existing tcpci_irq like above vender specific
handling as well:
tcpci->data->priv_events(tcpci, tcpci->data);

Li Jun
>
> static const struct regmap_config tcpci_regmap_config = {
> .reg_bits = 8,
> @@ -435,22 +479,18 @@ static int tcpci_parse_config(struct tcpci *tcpci)
> return 0;
> }
>
> -static int tcpci_probe(struct i2c_client *client,
> - const struct i2c_device_id *i2c_id)
> +struct tcpci *tcpci_register_port(struct device *dev, struct tcpci_data
> +*data)
> {
> struct tcpci *tcpci;
> int err;
>
> - tcpci = devm_kzalloc(&client->dev, sizeof(*tcpci), GFP_KERNEL);
> + tcpci = devm_kzalloc(dev, sizeof(*tcpci), GFP_KERNEL);
> if (!tcpci)
> - return -ENOMEM;
> + return ERR_PTR(-ENOMEM);
>
> - tcpci->client = client;
> - tcpci->dev = &client->dev;
> - i2c_set_clientdata(client, tcpci);
> - tcpci->regmap = devm_regmap_init_i2c(client, &tcpci_regmap_config);
> - if (IS_ERR(tcpci->regmap))
> - return PTR_ERR(tcpci->regmap);
> + tcpci->dev = dev;
> + tcpci->data = data;
> + tcpci->regmap = data->regmap;
>
> tcpci->tcpc.init = tcpci_init;
> tcpci->tcpc.get_vbus = tcpci_get_vbus; @@ -467,27 +507,63 @@ static
> int tcpci_probe(struct i2c_client *client,
>
> err = tcpci_parse_config(tcpci);
> if (err < 0)
> - return err;
> + return ERR_PTR(err);
> +
> + tcpci->port = tcpm_register_port(tcpci->dev, &tcpci->tcpc);
> + if (PTR_ERR_OR_ZERO(tcpci->port))
> + return ERR_CAST(tcpci->port);
>
> - /* Disable chip interrupts */
> - tcpci_write16(tcpci, TCPC_ALERT_MASK, 0);
> + return tcpci;
> +}
> +EXPORT_SYMBOL_GPL(tcpci_register_port);
> +
> +void tcpci_unregister_port(struct tcpci *tcpci) {
> + tcpm_unregister_port(tcpci->port);
> +}
> +EXPORT_SYMBOL_GPL(tcpci_unregister_port);
>
> - err = devm_request_threaded_irq(tcpci->dev, client->irq, NULL,
> - tcpci_irq,
> +static int tcpci_probe(struct i2c_client *client,
> + const struct i2c_device_id *i2c_id) {
> + struct tcpci_chip *chip;
> + int err;
> + u16 val = 0;
> +
> + chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
> + if (!chip)
> + return -ENOMEM;
> +
> + chip->data.regmap = devm_regmap_init_i2c(client,
> &tcpci_regmap_config);
> + if (IS_ERR(chip->data.regmap))
> + return PTR_ERR(chip->data.regmap);
> +
> + /* Disable chip interrupts before requesting irq */
> + err = regmap_raw_write(chip->data.regmap, TCPC_ALERT_MASK, &val,
> + sizeof(u16));
> + if (err < 0)
> + return err;
> +
> + err = devm_request_threaded_irq(&client->dev, client->irq, NULL,
> + _tcpci_irq,
> IRQF_ONESHOT | IRQF_TRIGGER_LOW,
> - dev_name(tcpci->dev), tcpci);
> + dev_name(&client->dev), chip);
> if (err < 0)
> return err;
>
> - tcpci->port = tcpm_register_port(tcpci->dev, &tcpci->tcpc);
> - return PTR_ERR_OR_ZERO(tcpci->port);
> + chip->tcpci = tcpci_register_port(&client->dev, &chip->data);
> + if (PTR_ERR_OR_ZERO(chip->tcpci))
> + return PTR_ERR(chip->tcpci);
> +
> + i2c_set_clientdata(client, chip);
> + return 0;
> }
>
> static int tcpci_remove(struct i2c_client *client) {
> - struct tcpci *tcpci = i2c_get_clientdata(client);
> + struct tcpci_chip *chip = i2c_get_clientdata(client);
>
> - tcpm_unregister_port(tcpci->port);
> + tcpci_unregister_port(chip->tcpci);
>
> return 0;
> }
> diff --git a/drivers/staging/typec/tcpci.h b/drivers/staging/typec/tcpci.h
> index fdfb06c..40025b2 100644
> --- a/drivers/staging/typec/tcpci.h
> +++ b/drivers/staging/typec/tcpci.h
> @@ -59,6 +59,7 @@
> #define TCPC_POWER_CTRL_VCONN_ENABLE BIT(0)
>
> #define TCPC_CC_STATUS 0x1d
> +#define TCPC_CC_STATUS_DRPRST BIT(5)
> #define TCPC_CC_STATUS_TERM BIT(4)
> #define TCPC_CC_STATUS_CC2_SHIFT 2
> #define TCPC_CC_STATUS_CC2_MASK 0x3
> @@ -121,4 +122,16 @@
> #define TCPC_VBUS_VOLTAGE_ALARM_HI_CFG 0x76
> #define TCPC_VBUS_VOLTAGE_ALARM_LO_CFG 0x78
>
> +struct tcpci;
> +struct tcpci_data {
> + struct regmap *regmap;
> + int (*init)(struct tcpci *tcpci, struct tcpci_data *data);
> + int (*set_vconn)(struct tcpci *tcpci, struct tcpci_data *data,
> + bool enable);
> +};
> +
> +struct tcpci *tcpci_register_port(struct device *dev, struct tcpci_data
> +*data); void tcpci_unregister_port(struct tcpci *tcpci); irqreturn_t
> +tcpci_irq(struct tcpci *tcpci);
> +
> #endif /* __LINUX_USB_TCPCI_H */
> --
> 1.9.1
>
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Next message: Christophe LEROY: "Re: [PATCH 4.14, 4.9] crypto: talitos - fix Kernel Oops on hashing an empty file"
Previous message: Peter Zijlstra: "Re: [PATCH RFC tools/lkmm 10/12] tools/memory-model: Add a S lock-based external-view litmus test"
In reply to: Guenter Roeck: "Re: [PATCH] staging: typec: handle vendor defined part and modify drp toggling flow"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]