linux-kernel - [PATCH 03/15] usb: typec: tcpci: use GENMASK() for TCPC_CC_STATUS

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Message-Id: <20240710-tcpc-cleanup-v1-3-0ec1f41f4263@linaro.org>
Date: Wed, 10 Jul 2024 11:36:10 +0100
From: André Draszik <andre.draszik@...aro.org>
To: Heikki Krogerus <heikki.krogerus@...ux.intel.com>, 
 Greg Kroah-Hartman <gregkh@...uxfoundation.org>
Cc: Peter Griffin <peter.griffin@...aro.org>, 
 Tudor Ambarus <tudor.ambarus@...aro.org>, 
 Will McVicker <willmcvicker@...gle.com>, 
 Badhri Jagan Sridharan <badhri@...gle.com>, kernel-team@...roid.com, 
 linux-usb@...r.kernel.org, linux-kernel@...r.kernel.org, 
 André Draszik <andre.draszik@...aro.org>
Subject: [PATCH 03/15] usb: typec: tcpci: use GENMASK() for
 TCPC_CC_STATUS_CC[12]

The existing code here, particularly in maxim_contaminant.c, is
arguably quite hard to read due to the open-coded masking and shifting
spanning multiple lines.

Use GENMASK() and FIELD_GET() instead, which arguably make the code
much easier to follow.

While at it, use the symbolic name TCPC_CC_STATE_SRC_OPEN for one
instance of open-coded 0x0.

Signed-off-by: André Draszik <andre.draszik@...aro.org>
---
 drivers/usb/typec/tcpm/maxim_contaminant.c | 8 +++-----
 drivers/usb/typec/tcpm/tcpci.c             | 7 +++----
 drivers/usb/typec/tcpm/tcpci_rt1711h.c     | 7 +++----
 include/linux/usb/tcpci.h                  | 8 +++-----
 4 files changed, 12 insertions(+), 18 deletions(-)

diff --git a/drivers/usb/typec/tcpm/maxim_contaminant.c b/drivers/usb/typec/tcpm/maxim_contaminant.c
index f8504a90da26..e7687aeb69c0 100644
--- a/drivers/usb/typec/tcpm/maxim_contaminant.c
+++ b/drivers/usb/typec/tcpm/maxim_contaminant.c
@@ -5,6 +5,7 @@
  * USB-C module to reduce wakeups due to contaminants.
  */
 
+#include <linux/bitfield.h>
 #include <linux/device.h>
 #include <linux/irqreturn.h>
 #include <linux/module.h>
@@ -48,11 +49,8 @@ enum fladc_select {
 #define STATUS_CHECK(reg, mask, val)	(((reg) & (mask)) == (val))
 
 #define IS_CC_OPEN(cc_status) \
-	(STATUS_CHECK((cc_status), TCPC_CC_STATUS_CC1_MASK << TCPC_CC_STATUS_CC1_SHIFT,  \
-		      TCPC_CC_STATE_SRC_OPEN) && STATUS_CHECK((cc_status),               \
-							      TCPC_CC_STATUS_CC2_MASK << \
-							      TCPC_CC_STATUS_CC2_SHIFT,  \
-							      TCPC_CC_STATE_SRC_OPEN))
+	(FIELD_GET(TCPC_CC_STATUS_CC1, cc_status) == TCPC_CC_STATE_SRC_OPEN \
+	 && FIELD_GET(TCPC_CC_STATUS_CC2, cc_status) == TCPC_CC_STATE_SRC_OPEN)
 
 static int max_contaminant_adc_to_mv(struct max_tcpci_chip *chip, enum fladc_select channel,
 				     bool ua_src, u8 fladc)
diff --git a/drivers/usb/typec/tcpm/tcpci.c b/drivers/usb/typec/tcpm/tcpci.c
index 8a18d561b063..ce11a154c7dc 100644
--- a/drivers/usb/typec/tcpm/tcpci.c
+++ b/drivers/usb/typec/tcpm/tcpci.c
@@ -5,6 +5,7 @@
  * USB Type-C Port Controller Interface.
  */
 
+#include <linux/bitfield.h>
 #include <linux/delay.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
@@ -241,12 +242,10 @@ static int tcpci_get_cc(struct tcpc_dev *tcpc,
 	if (ret < 0)
 		return ret;
 
-	*cc1 = tcpci_to_typec_cc((reg >> TCPC_CC_STATUS_CC1_SHIFT) &
-				 TCPC_CC_STATUS_CC1_MASK,
+	*cc1 = tcpci_to_typec_cc(FIELD_GET(TCPC_CC_STATUS_CC1, reg),
 				 reg & TCPC_CC_STATUS_TERM ||
 				 tcpc_presenting_rd(role_control, CC1));
-	*cc2 = tcpci_to_typec_cc((reg >> TCPC_CC_STATUS_CC2_SHIFT) &
-				 TCPC_CC_STATUS_CC2_MASK,
+	*cc2 = tcpci_to_typec_cc(FIELD_GET(TCPC_CC_STATUS_CC2, reg),
 				 reg & TCPC_CC_STATUS_TERM ||
 				 tcpc_presenting_rd(role_control, CC2));
 
diff --git a/drivers/usb/typec/tcpm/tcpci_rt1711h.c b/drivers/usb/typec/tcpm/tcpci_rt1711h.c
index 67422d45eb54..c6dbccf6b17a 100644
--- a/drivers/usb/typec/tcpm/tcpci_rt1711h.c
+++ b/drivers/usb/typec/tcpm/tcpci_rt1711h.c
@@ -5,6 +5,7 @@
  * Richtek RT1711H Type-C Chip Driver
  */
 
+#include <linux/bitfield.h>
 #include <linux/bits.h>
 #include <linux/kernel.h>
 #include <linux/mod_devicetable.h>
@@ -195,12 +196,10 @@ static inline int rt1711h_init_cc_params(struct rt1711h_chip *chip, u8 status)
 	if (ret < 0)
 		return ret;
 
-	cc1 = tcpci_to_typec_cc((status >> TCPC_CC_STATUS_CC1_SHIFT) &
-				TCPC_CC_STATUS_CC1_MASK,
+	cc1 = tcpci_to_typec_cc(FIELD_GET(TCPC_CC_STATUS_CC1, status),
 				status & TCPC_CC_STATUS_TERM ||
 				tcpc_presenting_rd(role, CC1));
-	cc2 = tcpci_to_typec_cc((status >> TCPC_CC_STATUS_CC2_SHIFT) &
-				TCPC_CC_STATUS_CC2_MASK,
+	cc2 = tcpci_to_typec_cc(FIELD_GET(TCPC_CC_STATUS_CC2, status),
 				status & TCPC_CC_STATUS_TERM ||
 				tcpc_presenting_rd(role, CC2));
 
diff --git a/include/linux/usb/tcpci.h b/include/linux/usb/tcpci.h
index d27fe0c22a8b..31d21ccf662b 100644
--- a/include/linux/usb/tcpci.h
+++ b/include/linux/usb/tcpci.h
@@ -92,11 +92,9 @@
 #define TCPC_CC_STATUS_TERM		BIT(4)
 #define TCPC_CC_STATUS_TERM_RP		0
 #define TCPC_CC_STATUS_TERM_RD		1
+#define TCPC_CC_STATUS_CC2		GENMASK(3, 2)
+#define TCPC_CC_STATUS_CC1		GENMASK(1, 0)
 #define TCPC_CC_STATE_SRC_OPEN		0
-#define TCPC_CC_STATUS_CC2_SHIFT	2
-#define TCPC_CC_STATUS_CC2_MASK		0x3
-#define TCPC_CC_STATUS_CC1_SHIFT	0
-#define TCPC_CC_STATUS_CC1_MASK		0x3
 
 #define TCPC_POWER_STATUS		0x1e
 #define TCPC_POWER_STATUS_DBG_ACC_CON	BIT(7)
@@ -256,7 +254,7 @@ static inline enum typec_cc_status tcpci_to_typec_cc(unsigned int cc, bool sink)
 		if (sink)
 			return TYPEC_CC_RP_3_0;
 		fallthrough;
-	case 0x0:
+	case TCPC_CC_STATE_SRC_OPEN:
 	default:
 		return TYPEC_CC_OPEN;
 	}

-- 
2.45.2.803.g4e1b14247a-goog