[PATCH AUTOSEL 6.5 06/18] phy: qualcomm: phy-qcom-eusb2-repeater: Zero out untouched tuning regs

From: Sasha Levin
Date: Tue Nov 07 2023 - 18:24:52 EST


From: Konrad Dybcio <konrad.dybcio@xxxxxxxxxx>

[ Upstream commit 99a517a582fc1272d1d3cf3b9e671a14d7db77b8 ]

The vendor kernel zeroes out all tuning data outside the init sequence
as part of initialization. Follow suit to avoid UB.

Signed-off-by: Konrad Dybcio <konrad.dybcio@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20230830-topic-eusb2_override-v2-3-7d8c893d93f6@xxxxxxxxxx
Signed-off-by: Vinod Koul <vkoul@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
.../phy/qualcomm/phy-qcom-eusb2-repeater.c | 58 ++++++++++++++-----
1 file changed, 44 insertions(+), 14 deletions(-)

diff --git a/drivers/phy/qualcomm/phy-qcom-eusb2-repeater.c b/drivers/phy/qualcomm/phy-qcom-eusb2-repeater.c
index b20b805414a2a..6777532dd4dc9 100644
--- a/drivers/phy/qualcomm/phy-qcom-eusb2-repeater.c
+++ b/drivers/phy/qualcomm/phy-qcom-eusb2-repeater.c
@@ -25,9 +25,18 @@
#define EUSB2_FORCE_VAL_5 0xeD
#define V_CLK_19P2M_EN BIT(6)

+#define EUSB2_TUNE_USB2_CROSSOVER 0x50
#define EUSB2_TUNE_IUSB2 0x51
+#define EUSB2_TUNE_RES_FSDIF 0x52
+#define EUSB2_TUNE_HSDISC 0x53
#define EUSB2_TUNE_SQUELCH_U 0x54
+#define EUSB2_TUNE_USB2_SLEW 0x55
+#define EUSB2_TUNE_USB2_EQU 0x56
#define EUSB2_TUNE_USB2_PREEM 0x57
+#define EUSB2_TUNE_USB2_HS_COMP_CUR 0x58
+#define EUSB2_TUNE_EUSB_SLEW 0x59
+#define EUSB2_TUNE_EUSB_EQU 0x5A
+#define EUSB2_TUNE_EUSB_HS_COMP_CUR 0x5B

#define QCOM_EUSB2_REPEATER_INIT_CFG(r, v) \
{ \
@@ -36,9 +45,18 @@
}

enum reg_fields {
+ F_TUNE_EUSB_HS_COMP_CUR,
+ F_TUNE_EUSB_EQU,
+ F_TUNE_EUSB_SLEW,
+ F_TUNE_USB2_HS_COMP_CUR,
F_TUNE_USB2_PREEM,
+ F_TUNE_USB2_EQU,
+ F_TUNE_USB2_SLEW,
F_TUNE_SQUELCH_U,
+ F_TUNE_HSDISC,
+ F_TUNE_RES_FSDIF,
F_TUNE_IUSB2,
+ F_TUNE_USB2_CROSSOVER,
F_NUM_TUNE_FIELDS,

F_FORCE_VAL_5 = F_NUM_TUNE_FIELDS,
@@ -51,9 +69,18 @@ enum reg_fields {
};

static struct reg_field eusb2_repeater_tune_reg_fields[F_NUM_FIELDS] = {
+ [F_TUNE_EUSB_HS_COMP_CUR] = REG_FIELD(EUSB2_TUNE_EUSB_HS_COMP_CUR, 0, 1),
+ [F_TUNE_EUSB_EQU] = REG_FIELD(EUSB2_TUNE_EUSB_EQU, 0, 1),
+ [F_TUNE_EUSB_SLEW] = REG_FIELD(EUSB2_TUNE_EUSB_SLEW, 0, 1),
+ [F_TUNE_USB2_HS_COMP_CUR] = REG_FIELD(EUSB2_TUNE_USB2_HS_COMP_CUR, 0, 1),
[F_TUNE_USB2_PREEM] = REG_FIELD(EUSB2_TUNE_USB2_PREEM, 0, 2),
+ [F_TUNE_USB2_EQU] = REG_FIELD(EUSB2_TUNE_USB2_EQU, 0, 1),
+ [F_TUNE_USB2_SLEW] = REG_FIELD(EUSB2_TUNE_USB2_SLEW, 0, 1),
[F_TUNE_SQUELCH_U] = REG_FIELD(EUSB2_TUNE_SQUELCH_U, 0, 2),
+ [F_TUNE_HSDISC] = REG_FIELD(EUSB2_TUNE_HSDISC, 0, 2),
+ [F_TUNE_RES_FSDIF] = REG_FIELD(EUSB2_TUNE_RES_FSDIF, 0, 2),
[F_TUNE_IUSB2] = REG_FIELD(EUSB2_TUNE_IUSB2, 0, 3),
+ [F_TUNE_USB2_CROSSOVER] = REG_FIELD(EUSB2_TUNE_USB2_CROSSOVER, 0, 2),

[F_FORCE_VAL_5] = REG_FIELD(EUSB2_FORCE_VAL_5, 0, 7),
[F_FORCE_EN_5] = REG_FIELD(EUSB2_FORCE_EN_5, 0, 7),
@@ -63,13 +90,8 @@ static struct reg_field eusb2_repeater_tune_reg_fields[F_NUM_FIELDS] = {
[F_RPTR_STATUS] = REG_FIELD(EUSB2_RPTR_STATUS, 0, 7),
};

-struct eusb2_repeater_init_tbl {
- unsigned int reg;
- unsigned int val;
-};
-
struct eusb2_repeater_cfg {
- const struct eusb2_repeater_init_tbl *init_tbl;
+ const u32 *init_tbl;
int init_tbl_num;
const char * const *vreg_list;
int num_vregs;
@@ -88,10 +110,10 @@ static const char * const pm8550b_vreg_l[] = {
"vdd18", "vdd3",
};

-static const struct eusb2_repeater_init_tbl pm8550b_init_tbl[] = {
- QCOM_EUSB2_REPEATER_INIT_CFG(F_TUNE_IUSB2, 0x8),
- QCOM_EUSB2_REPEATER_INIT_CFG(F_TUNE_SQUELCH_U, 0x3),
- QCOM_EUSB2_REPEATER_INIT_CFG(F_TUNE_USB2_PREEM, 0x5),
+static const u32 pm8550b_init_tbl[F_NUM_TUNE_FIELDS] = {
+ [F_TUNE_IUSB2] = 0x8,
+ [F_TUNE_SQUELCH_U] = 0x3,
+ [F_TUNE_USB2_PREEM] = 0x5,
};

static const struct eusb2_repeater_cfg pm8550b_eusb2_cfg = {
@@ -119,8 +141,9 @@ static int eusb2_repeater_init_vregs(struct eusb2_repeater *rptr)

static int eusb2_repeater_init(struct phy *phy)
{
+ struct reg_field *regfields = eusb2_repeater_tune_reg_fields;
struct eusb2_repeater *rptr = phy_get_drvdata(phy);
- const struct eusb2_repeater_init_tbl *init_tbl = rptr->cfg->init_tbl;
+ const u32 *init_tbl = rptr->cfg->init_tbl;
u32 val;
int ret;
int i;
@@ -131,9 +154,16 @@ static int eusb2_repeater_init(struct phy *phy)

regmap_field_update_bits(rptr->regs[F_EN_CTL1], EUSB2_RPTR_EN, EUSB2_RPTR_EN);

- for (i = 0; i < rptr->cfg->init_tbl_num; i++)
- regmap_field_update_bits(rptr->regs[init_tbl[i].reg],
- init_tbl[i].val, init_tbl[i].val);
+ for (i = 0; i < F_NUM_TUNE_FIELDS; i++) {
+ if (init_tbl[i]) {
+ regmap_field_update_bits(rptr->regs[i], init_tbl[i], init_tbl[i]);
+ } else {
+ /* Write 0 if there's no value set */
+ u32 mask = GENMASK(regfields[i].msb, regfields[i].lsb);
+
+ regmap_field_update_bits(rptr->regs[i], mask, 0);
+ }
+ }

ret = regmap_field_read_poll_timeout(rptr->regs[F_RPTR_STATUS],
val, val & RPTR_OK, 10, 5);
--
2.42.0