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usb: typec: tcpci: Add support when hidden tx registers are inaccessible

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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.

Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Badhri Jagan Sridharan <badhri@google.com>
Link: https://lore.kernel.org/r/20200901025927.3596190-3-badhri@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Badhri Jagan Sridharan 2020-08-31 19:59:15 -07:00 committed by Greg Kroah-Hartman
parent 492c1dc9d0
commit 19b6547683
2 changed files with 43 additions and 11 deletions
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46
drivers/usb/typec/tcpm/tcpci.c
View File

@ -330,23 +330,47 @@ 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) {
u8 buf[TCPC_TRANSMIT_BUFFER_MAX_LEN] = {0,};
u8 pos = 0;
ret = tcpci_write16(tcpci, TCPC_TX_HDR, header);
if (ret < 0)
return ret;
/* Payload + header + TCPC_TX_BYTE_CNT */
buf[pos++] = cnt + 2;
if (cnt > 0) {
ret = regmap_raw_write(tcpci->regmap, TCPC_TX_DATA,
&msg->payload, cnt);
if (msg)
memcpy(&buf[pos], &msg->header, sizeof(msg->header));
pos += sizeof(header);
if (cnt > 0)
memcpy(&buf[pos], msg->payload, cnt);
pos += cnt;
ret = regmap_raw_write(tcpci->regmap, TCPC_TX_BYTE_CNT, buf, pos);
if (ret < 0)
return ret;
} else {
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;
if (cnt > 0) {
ret = regmap_raw_write(tcpci->regmap, TCPC_TX_DATA, &msg->payload, cnt);
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;

8
drivers/usb/typec/tcpm/tcpci.h
View File

@ -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);