The 2 callers of fusb302_set_cc_polarity both call fusb302_set_cc_pull
directly before calling fusb302_set_cc_polarity, this is not ideal for
2 reasons:
1) fusb302_set_cc_pull uses the cached polarity when applying pull-ups,
which maybe changed immediately afterwards, to fix this set_cc_polarity
already does the pull-up setting.
2) Both touch the SWITCHES0 register in a r-w-modify cycle, this leads to
read reg, write reg, read reg, write reg. If we fold the setting of
the pull-downs into fusb302_set_cc_polarity then not only can we avoid
doing the reads / writes twice, at this point we set all bits, so we
can skip the read, turning 4 (slowish) i2c-transfers into 1.
Doing this also avoids the need to cache the pull_up state in
struct fusb302_chip.
Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
---
drivers/usb/typec/tcpm/fusb302.c | 48 +++++++++++---------------------
1 file changed, 16 insertions(+), 32 deletions(-)
diff --git a/drivers/usb/typec/tcpm/fusb302.c b/drivers/usb/typec/tcpm/fusb302.c
index e9344997329c..d2cce67289d4 100644
--- a/drivers/usb/typec/tcpm/fusb302.c
+++ b/drivers/usb/typec/tcpm/fusb302.c
@@ -99,7 +99,6 @@ struct fusb302_chip {
bool intr_comp_chng;
/* port status */
- bool pull_up;
bool vconn_on;
bool vbus_on;
bool charge_on;
@@ -540,7 +539,6 @@ static int fusb302_set_cc_pull(struct fusb302_chip *chip,
mask, data);
if (ret < 0)
return ret;
- chip->pull_up = pull_up;
return ret;
}
@@ -1226,38 +1224,36 @@ static const char * const cc_polarity_name[] = {
[TYPEC_POLARITY_CC2] = "Polarity_CC2",
};
-static int fusb302_set_cc_polarity(struct fusb302_chip *chip,
- enum typec_cc_polarity cc_polarity)
+static int fusb302_set_cc_polarity_and_pull(struct fusb302_chip *chip,
+ enum typec_cc_polarity cc_polarity,
+ bool pull_up, bool pull_down)
{
int ret = 0;
- u8 switches0_mask = FUSB_REG_SWITCHES0_CC1_PU_EN |
- FUSB_REG_SWITCHES0_CC2_PU_EN |
- FUSB_REG_SWITCHES0_VCONN_CC1 |
- FUSB_REG_SWITCHES0_VCONN_CC2 |
- FUSB_REG_SWITCHES0_MEAS_CC1 |
- FUSB_REG_SWITCHES0_MEAS_CC2;
u8 switches0_data = 0x00;
u8 switches1_mask = FUSB_REG_SWITCHES1_TXCC1_EN |
FUSB_REG_SWITCHES1_TXCC2_EN;
u8 switches1_data = 0x00;
+ if (pull_down)
+ switches0_data |= FUSB_REG_SWITCHES0_CC1_PD_EN |
+ FUSB_REG_SWITCHES0_CC2_PD_EN;
+
if (cc_polarity == TYPEC_POLARITY_CC1) {
- switches0_data = FUSB_REG_SWITCHES0_MEAS_CC1;
+ switches0_data |= FUSB_REG_SWITCHES0_MEAS_CC1;
if (chip->vconn_on)
switches0_data |= FUSB_REG_SWITCHES0_VCONN_CC2;
- if (chip->pull_up)
+ if (pull_up)
switches0_data |= FUSB_REG_SWITCHES0_CC1_PU_EN;
switches1_data = FUSB_REG_SWITCHES1_TXCC1_EN;
} else {
- switches0_data = FUSB_REG_SWITCHES0_MEAS_CC2;
+ switches0_data |= FUSB_REG_SWITCHES0_MEAS_CC2;
if (chip->vconn_on)
switches0_data |= FUSB_REG_SWITCHES0_VCONN_CC1;
- if (chip->pull_up)
+ if (pull_up)
switches0_data |= FUSB_REG_SWITCHES0_CC2_PU_EN;
switches1_data = FUSB_REG_SWITCHES1_TXCC2_EN;
}
- ret = fusb302_i2c_mask_write(chip, FUSB_REG_SWITCHES0,
- switches0_mask, switches0_data);
+ ret = fusb302_i2c_write(chip, FUSB_REG_SWITCHES0, switches0_data);
if (ret < 0)
return ret;
ret = fusb302_i2c_mask_write(chip, FUSB_REG_SWITCHES1,
@@ -1278,16 +1274,10 @@ static int fusb302_handle_togdone_snk(struct fusb302_chip *chip,
enum typec_cc_polarity cc_polarity;
enum typec_cc_status cc_status_active, cc1, cc2;
- /* set pull_up, pull_down */
- ret = fusb302_set_cc_pull(chip, false, true);
- if (ret < 0) {
- fusb302_log(chip, "cannot set cc to pull down, ret=%d", ret);
- return ret;
- }
- /* set polarity */
+ /* set polarity and pull_up, pull_down */
cc_polarity = (togdone_result == FUSB_REG_STATUS1A_TOGSS_SNK1) ?
TYPEC_POLARITY_CC1 : TYPEC_POLARITY_CC2;
- ret = fusb302_set_cc_polarity(chip, cc_polarity);
+ ret = fusb302_set_cc_polarity_and_pull(chip, cc_polarity, false, true);
if (ret < 0) {
fusb302_log(chip, "cannot set cc polarity %s, ret=%d",
cc_polarity_name[cc_polarity], ret);
@@ -1354,16 +1344,10 @@ static int fusb302_handle_togdone_src(struct fusb302_chip *chip,
enum typec_cc_polarity cc_polarity;
enum typec_cc_status cc_status_active, cc1, cc2;
- /* set pull_up, pull_down */
- ret = fusb302_set_cc_pull(chip, true, false);
- if (ret < 0) {
- fusb302_log(chip, "cannot set cc to pull up, ret=%d", ret);
- return ret;
- }
- /* set polarity */
+ /* set polarity and pull_up, pull_down */
cc_polarity = (togdone_result == FUSB_REG_STATUS1A_TOGSS_SRC1) ?
TYPEC_POLARITY_CC1 : TYPEC_POLARITY_CC2;
- ret = fusb302_set_cc_polarity(chip, cc_polarity);
+ ret = fusb302_set_cc_polarity_and_pull(chip, cc_polarity, true, false);
if (ret < 0) {
fusb302_log(chip, "cannot set cc polarity %s, ret=%d",
cc_polarity_name[cc_polarity], ret);
--
2.20.1
