From d5e0d9187abd5e3ce23884c375c4b36f403e42be Mon Sep 17 00:00:00 2001
From: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Date: Thu, 4 Jan 2018 11:05:30 -0800
Subject: Input: libps2 - fix switch statement formatting

Individual labels of switch statements should have the same indentation
level as the switch statement itself.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
---
 drivers/input/serio/libps2.c | 131 +++++++++++++++++++++----------------------
 1 file changed, 65 insertions(+), 66 deletions(-)

(limited to 'drivers/input/serio')

diff --git a/drivers/input/serio/libps2.c b/drivers/input/serio/libps2.c
index 83e9c663aa67..21aea5169a99 100644
--- a/drivers/input/serio/libps2.c
+++ b/drivers/input/serio/libps2.c
@@ -126,46 +126,46 @@ EXPORT_SYMBOL(ps2_is_keyboard_id);
 static int ps2_adjust_timeout(struct ps2dev *ps2dev, int command, int timeout)
 {
 	switch (command) {
-		case PS2_CMD_RESET_BAT:
-			/*
-			 * Device has sent the first response byte after
-			 * reset command, reset is thus done, so we can
-			 * shorten the timeout.
-			 * The next byte will come soon (keyboard) or not
-			 * at all (mouse).
-			 */
-			if (timeout > msecs_to_jiffies(100))
-				timeout = msecs_to_jiffies(100);
-			break;
+	case PS2_CMD_RESET_BAT:
+		/*
+		 * Device has sent the first response byte after
+		 * reset command, reset is thus done, so we can
+		 * shorten the timeout.
+		 * The next byte will come soon (keyboard) or not
+		 * at all (mouse).
+		 */
+		if (timeout > msecs_to_jiffies(100))
+			timeout = msecs_to_jiffies(100);
+		break;
 
-		case PS2_CMD_GETID:
-			/*
-			 * Microsoft Natural Elite keyboard responds to
-			 * the GET ID command as it were a mouse, with
-			 * a single byte. Fail the command so atkbd will
-			 * use alternative probe to detect it.
-			 */
-			if (ps2dev->cmdbuf[1] == 0xaa) {
-				serio_pause_rx(ps2dev->serio);
-				ps2dev->flags = 0;
-				serio_continue_rx(ps2dev->serio);
-				timeout = 0;
-			}
-
-			/*
-			 * If device behind the port is not a keyboard there
-			 * won't be 2nd byte of ID response.
-			 */
-			if (!ps2_is_keyboard_id(ps2dev->cmdbuf[1])) {
-				serio_pause_rx(ps2dev->serio);
-				ps2dev->flags = ps2dev->cmdcnt = 0;
-				serio_continue_rx(ps2dev->serio);
-				timeout = 0;
-			}
-			break;
+	case PS2_CMD_GETID:
+		/*
+		 * Microsoft Natural Elite keyboard responds to
+		 * the GET ID command as it were a mouse, with
+		 * a single byte. Fail the command so atkbd will
+		 * use alternative probe to detect it.
+		 */
+		if (ps2dev->cmdbuf[1] == 0xaa) {
+			serio_pause_rx(ps2dev->serio);
+			ps2dev->flags = 0;
+			serio_continue_rx(ps2dev->serio);
+			timeout = 0;
+		}
 
-		default:
-			break;
+		/*
+		 * If device behind the port is not a keyboard there
+		 * won't be 2nd byte of ID response.
+		 */
+		if (!ps2_is_keyboard_id(ps2dev->cmdbuf[1])) {
+			serio_pause_rx(ps2dev->serio);
+			ps2dev->flags = ps2dev->cmdcnt = 0;
+			serio_continue_rx(ps2dev->serio);
+			timeout = 0;
+		}
+		break;
+
+	default:
+		break;
 	}
 
 	return timeout;
@@ -289,39 +289,38 @@ EXPORT_SYMBOL(ps2_init);
 int ps2_handle_ack(struct ps2dev *ps2dev, unsigned char data)
 {
 	switch (data) {
-		case PS2_RET_ACK:
-			ps2dev->nak = 0;
+	case PS2_RET_ACK:
+		ps2dev->nak = 0;
+		break;
+
+	case PS2_RET_NAK:
+		ps2dev->flags |= PS2_FLAG_NAK;
+		ps2dev->nak = PS2_RET_NAK;
+		break;
+
+	case PS2_RET_ERR:
+		if (ps2dev->flags & PS2_FLAG_NAK) {
+			ps2dev->flags &= ~PS2_FLAG_NAK;
+			ps2dev->nak = PS2_RET_ERR;
 			break;
+		}
 
-		case PS2_RET_NAK:
-			ps2dev->flags |= PS2_FLAG_NAK;
-			ps2dev->nak = PS2_RET_NAK;
+	/*
+	 * Workaround for mice which don't ACK the Get ID command.
+	 * These are valid mouse IDs that we recognize.
+	 */
+	case 0x00:
+	case 0x03:
+	case 0x04:
+		if (ps2dev->flags & PS2_FLAG_WAITID) {
+			ps2dev->nak = 0;
 			break;
-
-		case PS2_RET_ERR:
-			if (ps2dev->flags & PS2_FLAG_NAK) {
-				ps2dev->flags &= ~PS2_FLAG_NAK;
-				ps2dev->nak = PS2_RET_ERR;
-				break;
-			}
-
-		/*
-		 * Workaround for mice which don't ACK the Get ID command.
-		 * These are valid mouse IDs that we recognize.
-		 */
-		case 0x00:
-		case 0x03:
-		case 0x04:
-			if (ps2dev->flags & PS2_FLAG_WAITID) {
-				ps2dev->nak = 0;
-				break;
-			}
-			/* Fall through */
-		default:
-			return 0;
+		}
+		/* Fall through */
+	default:
+		return 0;
 	}
 
-
 	if (!ps2dev->nak) {
 		ps2dev->flags &= ~PS2_FLAG_NAK;
 		if (ps2dev->cmdcnt)
-- 
cgit v1.2.3


From b28bad65c1fec47076ebee88b51b0dafa31f5065 Mon Sep 17 00:00:00 2001
From: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Date: Thu, 4 Jan 2018 10:58:48 -0800
Subject: Input: libps2 - use u8 for byte data

Instead of using unsigned char for the byte data switch to using u8. Also
use unsigned int for the command codes and timeouts, and have
ps2_handle_ack() and ps2_handle_response() return bool instead of int, as
they do not return error codes but rather signal whether a byte was handled
or not handled. ps2_is_keyboard_id() now returns bool as well.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
---
 drivers/input/serio/libps2.c | 31 ++++++++++++++++---------------
 include/linux/libps2.h       | 23 +++++++++++++----------
 2 files changed, 29 insertions(+), 25 deletions(-)

(limited to 'drivers/input/serio')

diff --git a/drivers/input/serio/libps2.c b/drivers/input/serio/libps2.c
index 21aea5169a99..c3712f0a47b5 100644
--- a/drivers/input/serio/libps2.c
+++ b/drivers/input/serio/libps2.c
@@ -34,7 +34,7 @@ MODULE_LICENSE("GPL");
  * ps2_sendbyte() can only be called from a process context.
  */
 
-int ps2_sendbyte(struct ps2dev *ps2dev, unsigned char byte, int timeout)
+int ps2_sendbyte(struct ps2dev *ps2dev, u8 byte, unsigned int timeout)
 {
 	serio_pause_rx(ps2dev->serio);
 	ps2dev->nak = 1;
@@ -75,7 +75,7 @@ EXPORT_SYMBOL(ps2_end_command);
  * and discards them.
  */
 
-void ps2_drain(struct ps2dev *ps2dev, int maxbytes, int timeout)
+void ps2_drain(struct ps2dev *ps2dev, size_t maxbytes, unsigned int timeout)
 {
 	if (maxbytes > sizeof(ps2dev->cmdbuf)) {
 		WARN_ON(1);
@@ -102,9 +102,9 @@ EXPORT_SYMBOL(ps2_drain);
  * known keyboard IDs.
  */
 
-int ps2_is_keyboard_id(char id_byte)
+bool ps2_is_keyboard_id(u8 id_byte)
 {
-	static const char keyboard_ids[] = {
+	static const u8 keyboard_ids[] = {
 		0xab,	/* Regular keyboards		*/
 		0xac,	/* NCD Sun keyboard		*/
 		0x2b,	/* Trust keyboard, translated	*/
@@ -123,7 +123,8 @@ EXPORT_SYMBOL(ps2_is_keyboard_id);
  * completion.
  */
 
-static int ps2_adjust_timeout(struct ps2dev *ps2dev, int command, int timeout)
+static int ps2_adjust_timeout(struct ps2dev *ps2dev,
+			      unsigned int command, unsigned int timeout)
 {
 	switch (command) {
 	case PS2_CMD_RESET_BAT:
@@ -178,11 +179,11 @@ static int ps2_adjust_timeout(struct ps2dev *ps2dev, int command, int timeout)
  * ps2_command() can only be called from a process context
  */
 
-int __ps2_command(struct ps2dev *ps2dev, unsigned char *param, int command)
+int __ps2_command(struct ps2dev *ps2dev, u8 *param, unsigned int command)
 {
-	int timeout;
-	int send = (command >> 12) & 0xf;
-	int receive = (command >> 8) & 0xf;
+	unsigned int timeout;
+	unsigned int send = (command >> 12) & 0xf;
+	unsigned int receive = (command >> 8) & 0xf;
 	int rc = -1;
 	int i;
 
@@ -256,7 +257,7 @@ int __ps2_command(struct ps2dev *ps2dev, unsigned char *param, int command)
 }
 EXPORT_SYMBOL(__ps2_command);
 
-int ps2_command(struct ps2dev *ps2dev, unsigned char *param, int command)
+int ps2_command(struct ps2dev *ps2dev, u8 *param, unsigned int command)
 {
 	int rc;
 
@@ -286,7 +287,7 @@ EXPORT_SYMBOL(ps2_init);
  * to properly process ACK/NAK of a command from a PS/2 device.
  */
 
-int ps2_handle_ack(struct ps2dev *ps2dev, unsigned char data)
+bool ps2_handle_ack(struct ps2dev *ps2dev, u8 data)
 {
 	switch (data) {
 	case PS2_RET_ACK:
@@ -318,7 +319,7 @@ int ps2_handle_ack(struct ps2dev *ps2dev, unsigned char data)
 		}
 		/* Fall through */
 	default:
-		return 0;
+		return false;
 	}
 
 	if (!ps2dev->nak) {
@@ -333,7 +334,7 @@ int ps2_handle_ack(struct ps2dev *ps2dev, unsigned char data)
 	if (data != PS2_RET_ACK)
 		ps2_handle_response(ps2dev, data);
 
-	return 1;
+	return true;
 }
 EXPORT_SYMBOL(ps2_handle_ack);
 
@@ -343,7 +344,7 @@ EXPORT_SYMBOL(ps2_handle_ack);
  * waiting for completion of the command.
  */
 
-int ps2_handle_response(struct ps2dev *ps2dev, unsigned char data)
+bool ps2_handle_response(struct ps2dev *ps2dev, u8 data)
 {
 	if (ps2dev->cmdcnt)
 		ps2dev->cmdbuf[--ps2dev->cmdcnt] = data;
@@ -359,7 +360,7 @@ int ps2_handle_response(struct ps2dev *ps2dev, unsigned char data)
 		wake_up(&ps2dev->wait);
 	}
 
-	return 1;
+	return true;
 }
 EXPORT_SYMBOL(ps2_handle_response);
 
diff --git a/include/linux/libps2.h b/include/linux/libps2.h
index 4ad06e824f76..04a5750f1e4e 100644
--- a/include/linux/libps2.h
+++ b/include/linux/libps2.h
@@ -10,6 +10,9 @@
  * the Free Software Foundation.
  */
 
+#include <linux/mutex.h>
+#include <linux/types.h>
+#include <linux/wait.h>
 
 #define PS2_CMD_GETID		0x02f2
 #define PS2_CMD_RESET_BAT	0x02ff
@@ -36,21 +39,21 @@ struct ps2dev {
 	wait_queue_head_t wait;
 
 	unsigned long flags;
-	unsigned char cmdbuf[8];
-	unsigned char cmdcnt;
-	unsigned char nak;
+	u8 cmdbuf[8];
+	u8 cmdcnt;
+	u8 nak;
 };
 
 void ps2_init(struct ps2dev *ps2dev, struct serio *serio);
-int ps2_sendbyte(struct ps2dev *ps2dev, unsigned char byte, int timeout);
-void ps2_drain(struct ps2dev *ps2dev, int maxbytes, int timeout);
+int ps2_sendbyte(struct ps2dev *ps2dev, u8 byte, unsigned int timeout);
+void ps2_drain(struct ps2dev *ps2dev, size_t maxbytes, unsigned int timeout);
 void ps2_begin_command(struct ps2dev *ps2dev);
 void ps2_end_command(struct ps2dev *ps2dev);
-int __ps2_command(struct ps2dev *ps2dev, unsigned char *param, int command);
-int ps2_command(struct ps2dev *ps2dev, unsigned char *param, int command);
-int ps2_handle_ack(struct ps2dev *ps2dev, unsigned char data);
-int ps2_handle_response(struct ps2dev *ps2dev, unsigned char data);
+int __ps2_command(struct ps2dev *ps2dev, u8 *param, unsigned int command);
+int ps2_command(struct ps2dev *ps2dev, u8 *param, unsigned int command);
+bool ps2_handle_ack(struct ps2dev *ps2dev, u8 data);
+bool ps2_handle_response(struct ps2dev *ps2dev, u8 data);
 void ps2_cmd_aborted(struct ps2dev *ps2dev);
-int ps2_is_keyboard_id(char id);
+bool ps2_is_keyboard_id(u8 id);
 
 #endif /* _LIBPS2_H */
-- 
cgit v1.2.3


From 08be954b7a7de6742d3d47e4dc20e3b086410761 Mon Sep 17 00:00:00 2001
From: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Date: Tue, 2 Jan 2018 12:03:02 -0800
Subject: Input: psmouse - move sliced command implementation to libps2

In preparation to adding some debugging statements to PS/2 control
sequences let's move psmouse_sliced_command() into libps2 and rename it
to ps2_sliced_command().

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
---
 drivers/input/mouse/elantech.c     | 12 ++++++------
 drivers/input/mouse/logips2pp.c    |  2 +-
 drivers/input/mouse/psmouse-base.c | 26 --------------------------
 drivers/input/mouse/psmouse.h      |  1 -
 drivers/input/mouse/synaptics.c    |  8 ++++----
 drivers/input/serio/libps2.c       | 32 ++++++++++++++++++++++++++++++++
 include/linux/libps2.h             |  3 +++
 7 files changed, 46 insertions(+), 38 deletions(-)

(limited to 'drivers/input/serio')

diff --git a/drivers/input/mouse/elantech.c b/drivers/input/mouse/elantech.c
index af7fc17c14d9..db47a5e1d114 100644
--- a/drivers/input/mouse/elantech.c
+++ b/drivers/input/mouse/elantech.c
@@ -35,7 +35,7 @@
 static int synaptics_send_cmd(struct psmouse *psmouse, unsigned char c,
 				unsigned char *param)
 {
-	if (psmouse_sliced_command(psmouse, c) ||
+	if (ps2_sliced_command(&psmouse->ps2dev, c) ||
 	    ps2_command(&psmouse->ps2dev, param, PSMOUSE_CMD_GETINFO)) {
 		psmouse_err(psmouse, "%s query 0x%02x failed.\n", __func__, c);
 		return -1;
@@ -107,8 +107,8 @@ static int elantech_read_reg(struct psmouse *psmouse, unsigned char reg,
 
 	switch (etd->hw_version) {
 	case 1:
-		if (psmouse_sliced_command(psmouse, ETP_REGISTER_READ) ||
-		    psmouse_sliced_command(psmouse, reg) ||
+		if (ps2_sliced_command(&psmouse->ps2dev, ETP_REGISTER_READ) ||
+		    ps2_sliced_command(&psmouse->ps2dev, reg) ||
 		    ps2_command(&psmouse->ps2dev, param, PSMOUSE_CMD_GETINFO)) {
 			rc = -1;
 		}
@@ -162,9 +162,9 @@ static int elantech_write_reg(struct psmouse *psmouse, unsigned char reg,
 
 	switch (etd->hw_version) {
 	case 1:
-		if (psmouse_sliced_command(psmouse, ETP_REGISTER_WRITE) ||
-		    psmouse_sliced_command(psmouse, reg) ||
-		    psmouse_sliced_command(psmouse, val) ||
+		if (ps2_sliced_command(&psmouse->ps2dev, ETP_REGISTER_WRITE) ||
+		    ps2_sliced_command(&psmouse->ps2dev, reg) ||
+		    ps2_sliced_command(&psmouse->ps2dev, val) ||
 		    ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_SETSCALE11)) {
 			rc = -1;
 		}
diff --git a/drivers/input/mouse/logips2pp.c b/drivers/input/mouse/logips2pp.c
index 3c8d7051ef5e..3d5637e6fa5f 100644
--- a/drivers/input/mouse/logips2pp.c
+++ b/drivers/input/mouse/logips2pp.c
@@ -117,7 +117,7 @@ static int ps2pp_cmd(struct psmouse *psmouse, u8 *param, u8 command)
 {
 	int error;
 
-	error = psmouse_sliced_command(psmouse, command);
+	error = ps2_sliced_command(&psmouse->ps2dev, command);
 	if (error)
 		return error;
 
diff --git a/drivers/input/mouse/psmouse-base.c b/drivers/input/mouse/psmouse-base.c
index f0b16eb4a32a..4f9f438e2653 100644
--- a/drivers/input/mouse/psmouse-base.c
+++ b/drivers/input/mouse/psmouse-base.c
@@ -431,32 +431,6 @@ static irqreturn_t psmouse_interrupt(struct serio *serio,
 	return IRQ_HANDLED;
 }
 
-/*
- * psmouse_sliced_command() sends an extended PS/2 command to the mouse
- * using sliced syntax, understood by advanced devices, such as Logitech
- * or Synaptics touchpads. The command is encoded as:
- * 0xE6 0xE8 rr 0xE8 ss 0xE8 tt 0xE8 uu where (rr*64)+(ss*16)+(tt*4)+uu
- * is the command.
- */
-int psmouse_sliced_command(struct psmouse *psmouse, u8 command)
-{
-	int i;
-	int error;
-
-	error = ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_SETSCALE11);
-	if (error)
-		return error;
-
-	for (i = 6; i >= 0; i -= 2) {
-		u8 d = (command >> i) & 3;
-		error = ps2_command(&psmouse->ps2dev, &d, PSMOUSE_CMD_SETRES);
-		if (error)
-			return error;
-	}
-
-	return 0;
-}
-
 /*
  * psmouse_reset() resets the mouse into power-on state.
  */
diff --git a/drivers/input/mouse/psmouse.h b/drivers/input/mouse/psmouse.h
index 8bc99691494e..71ac50082c8b 100644
--- a/drivers/input/mouse/psmouse.h
+++ b/drivers/input/mouse/psmouse.h
@@ -131,7 +131,6 @@ struct psmouse {
 
 void psmouse_queue_work(struct psmouse *psmouse, struct delayed_work *work,
 		unsigned long delay);
-int psmouse_sliced_command(struct psmouse *psmouse, unsigned char command);
 int psmouse_reset(struct psmouse *psmouse);
 void psmouse_set_state(struct psmouse *psmouse, enum psmouse_state new_state);
 void psmouse_set_resolution(struct psmouse *psmouse, unsigned int resolution);
diff --git a/drivers/input/mouse/synaptics.c b/drivers/input/mouse/synaptics.c
index cd9f61cb3fc6..89ab77a211b5 100644
--- a/drivers/input/mouse/synaptics.c
+++ b/drivers/input/mouse/synaptics.c
@@ -84,7 +84,7 @@ static int synaptics_mode_cmd(struct psmouse *psmouse, u8 mode)
 	u8 param[1];
 	int error;
 
-	error = psmouse_sliced_command(psmouse, mode);
+	error = ps2_sliced_command(&psmouse->ps2dev, mode);
 	if (error)
 		return error;
 
@@ -190,7 +190,7 @@ static int synaptics_send_cmd(struct psmouse *psmouse, u8 cmd, u8 *param)
 {
 	int error;
 
-	error = psmouse_sliced_command(psmouse, cmd);
+	error = ps2_sliced_command(&psmouse->ps2dev, cmd);
 	if (error)
 		return error;
 
@@ -547,7 +547,7 @@ static int synaptics_set_advanced_gesture_mode(struct psmouse *psmouse)
 	static u8 param = 0xc8;
 	int error;
 
-	error = psmouse_sliced_command(psmouse, SYN_QUE_MODEL);
+	error = ps2_sliced_command(&psmouse->ps2dev, SYN_QUE_MODEL);
 	if (error)
 		return error;
 
@@ -614,7 +614,7 @@ static int synaptics_pt_write(struct serio *serio, u8 c)
 	u8 rate_param = SYN_PS_CLIENT_CMD; /* indicates that we want pass-through port */
 	int error;
 
-	error = psmouse_sliced_command(parent, c);
+	error = ps2_sliced_command(&parent->ps2dev, c);
 	if (error)
 		return error;
 
diff --git a/drivers/input/serio/libps2.c b/drivers/input/serio/libps2.c
index c3712f0a47b5..e96ae477f0b5 100644
--- a/drivers/input/serio/libps2.c
+++ b/drivers/input/serio/libps2.c
@@ -269,6 +269,38 @@ int ps2_command(struct ps2dev *ps2dev, u8 *param, unsigned int command)
 }
 EXPORT_SYMBOL(ps2_command);
 
+/*
+ * ps2_sliced_command() sends an extended PS/2 command to the mouse
+ * using sliced syntax, understood by advanced devices, such as Logitech
+ * or Synaptics touchpads. The command is encoded as:
+ * 0xE6 0xE8 rr 0xE8 ss 0xE8 tt 0xE8 uu where (rr*64)+(ss*16)+(tt*4)+uu
+ * is the command.
+ */
+
+int ps2_sliced_command(struct ps2dev *ps2dev, u8 command)
+{
+	int i;
+	int retval;
+
+	ps2_begin_command(ps2dev);
+
+	retval = __ps2_command(ps2dev, NULL, PS2_CMD_SETSCALE11);
+	if (retval)
+		goto out;
+
+	for (i = 6; i >= 0; i -= 2) {
+		u8 d = (command >> i) & 3;
+		retval = __ps2_command(ps2dev, &d, PS2_CMD_SETRES);
+		if (retval)
+			break;
+	}
+
+out:
+	ps2_end_command(ps2dev);
+	return retval;
+}
+EXPORT_SYMBOL(ps2_sliced_command);
+
 /*
  * ps2_init() initializes ps2dev structure
  */
diff --git a/include/linux/libps2.h b/include/linux/libps2.h
index 646b581fea56..3c69cd796f48 100644
--- a/include/linux/libps2.h
+++ b/include/linux/libps2.h
@@ -15,6 +15,8 @@
 #include <linux/types.h>
 #include <linux/wait.h>
 
+#define PS2_CMD_SETSCALE11	0x00e6
+#define PS2_CMD_SETRES		0x10e8
 #define PS2_CMD_GETID		0x02f2
 #define PS2_CMD_RESET_BAT	0x02ff
 
@@ -52,6 +54,7 @@ void ps2_begin_command(struct ps2dev *ps2dev);
 void ps2_end_command(struct ps2dev *ps2dev);
 int __ps2_command(struct ps2dev *ps2dev, u8 *param, unsigned int command);
 int ps2_command(struct ps2dev *ps2dev, u8 *param, unsigned int command);
+int ps2_sliced_command(struct ps2dev *ps2dev, u8 command);
 bool ps2_handle_ack(struct ps2dev *ps2dev, u8 data);
 bool ps2_handle_response(struct ps2dev *ps2dev, u8 data);
 void ps2_cmd_aborted(struct ps2dev *ps2dev);
-- 
cgit v1.2.3


From 147b903da65daedc90dbeb66a75dd608a6a41ef2 Mon Sep 17 00:00:00 2001
From: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Date: Tue, 2 Jan 2018 12:21:49 -0800
Subject: Input: libps2 - add debugging statements

Debugging via i8042.debug and analyzing raw PS/2 data stream may be
cumbersome as you need to locate the boundaries of commands, decipher the
sliced commands, etc, etc. Let's add a bit more high level debug statements
for ps2_sendbyte(), ps2_command(), and ps2_sliced_command().

We do not introduce a new module parameter, but rater rely on the kernel
having dynamic debug facility enabled (which most everyone has nowadays).
Enable with:

echo "file libps2.c +pf" > /sys/kernel/debug/dynamic_debug/control

or add "libps2.dyndbg=+pf" to the kernel command line.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
---
 drivers/input/serio/libps2.c | 52 +++++++++++++++++++++++++++++++++-----------
 1 file changed, 39 insertions(+), 13 deletions(-)

(limited to 'drivers/input/serio')

diff --git a/drivers/input/serio/libps2.c b/drivers/input/serio/libps2.c
index e96ae477f0b5..82befae4dab0 100644
--- a/drivers/input/serio/libps2.c
+++ b/drivers/input/serio/libps2.c
@@ -26,22 +26,20 @@ MODULE_AUTHOR("Dmitry Torokhov <dtor@mail.ru>");
 MODULE_DESCRIPTION("PS/2 driver library");
 MODULE_LICENSE("GPL");
 
-/*
- * ps2_sendbyte() sends a byte to the device and waits for acknowledge.
- * It doesn't handle retransmission, though it could - because if there
- * is a need for retransmissions device has to be replaced anyway.
- *
- * ps2_sendbyte() can only be called from a process context.
- */
-
-int ps2_sendbyte(struct ps2dev *ps2dev, u8 byte, unsigned int timeout)
+static int ps2_do_sendbyte(struct ps2dev *ps2dev, u8 byte, unsigned int timeout)
 {
+	int error;
+
 	serio_pause_rx(ps2dev->serio);
 	ps2dev->nak = 1;
 	ps2dev->flags |= PS2_FLAG_ACK;
 	serio_continue_rx(ps2dev->serio);
 
-	if (serio_write(ps2dev->serio, byte) == 0)
+	error = serio_write(ps2dev->serio, byte);
+	if (error)
+		dev_dbg(&ps2dev->serio->dev,
+			"failed to write %#02x: %d\n", byte, error);
+	else
 		wait_event_timeout(ps2dev->wait,
 				   !(ps2dev->flags & PS2_FLAG_ACK),
 				   msecs_to_jiffies(timeout));
@@ -52,6 +50,24 @@ int ps2_sendbyte(struct ps2dev *ps2dev, u8 byte, unsigned int timeout)
 
 	return -ps2dev->nak;
 }
+
+/*
+ * ps2_sendbyte() sends a byte to the device and waits for acknowledge.
+ * It doesn't handle retransmission, though it could - because if there
+ * is a need for retransmissions device has to be replaced anyway.
+ *
+ * ps2_sendbyte() can only be called from a process context.
+ */
+
+int ps2_sendbyte(struct ps2dev *ps2dev, u8 byte, unsigned int timeout)
+{
+	int retval;
+
+	retval = ps2_do_sendbyte(ps2dev, byte, timeout);
+	dev_dbg(&ps2dev->serio->dev, "%02x - %x\n", byte, ps2dev->nak);
+
+	return retval;
+}
 EXPORT_SYMBOL(ps2_sendbyte);
 
 void ps2_begin_command(struct ps2dev *ps2dev)
@@ -186,6 +202,7 @@ int __ps2_command(struct ps2dev *ps2dev, u8 *param, unsigned int command)
 	unsigned int receive = (command >> 8) & 0xf;
 	int rc = -1;
 	int i;
+	u8 send_param[16];
 
 	if (receive > sizeof(ps2dev->cmdbuf)) {
 		WARN_ON(1);
@@ -197,6 +214,8 @@ int __ps2_command(struct ps2dev *ps2dev, u8 *param, unsigned int command)
 		return -1;
 	}
 
+	memcpy(send_param, param, send);
+
 	serio_pause_rx(ps2dev->serio);
 	ps2dev->flags = command == PS2_CMD_GETID ? PS2_FLAG_WAITID : 0;
 	ps2dev->cmdcnt = receive;
@@ -210,14 +229,14 @@ int __ps2_command(struct ps2dev *ps2dev, u8 *param, unsigned int command)
 	 * ACKing the reset command, and so it can take a long
 	 * time before the ACK arrives.
 	 */
-	if (ps2_sendbyte(ps2dev, command & 0xff,
-			 command == PS2_CMD_RESET_BAT ? 1000 : 200)) {
+	if (ps2_do_sendbyte(ps2dev, command & 0xff,
+			    command == PS2_CMD_RESET_BAT ? 1000 : 200)) {
 		serio_pause_rx(ps2dev->serio);
 		goto out_reset_flags;
 	}
 
 	for (i = 0; i < send; i++) {
-		if (ps2_sendbyte(ps2dev, param[i], 200)) {
+		if (ps2_do_sendbyte(ps2dev, param[i], 200)) {
 			serio_pause_rx(ps2dev->serio);
 			goto out_reset_flags;
 		}
@@ -253,6 +272,12 @@ int __ps2_command(struct ps2dev *ps2dev, u8 *param, unsigned int command)
 	ps2dev->flags = 0;
 	serio_continue_rx(ps2dev->serio);
 
+	dev_dbg(&ps2dev->serio->dev,
+		"%02x [%*ph] - %x/%08lx [%*ph]\n",
+		command & 0xff, send, send_param,
+		ps2dev->nak, ps2dev->flags,
+		receive, param ?: send_param);
+
 	return rc;
 }
 EXPORT_SYMBOL(__ps2_command);
@@ -296,6 +321,7 @@ int ps2_sliced_command(struct ps2dev *ps2dev, u8 command)
 	}
 
 out:
+	dev_dbg(&ps2dev->serio->dev, "%02x - %d\n", command, retval);
 	ps2_end_command(ps2dev);
 	return retval;
 }
-- 
cgit v1.2.3


From b99e1f2a1a3f4158bed9b9e9e97ac46678d8c2ac Mon Sep 17 00:00:00 2001
From: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Date: Thu, 4 Jan 2018 22:01:43 -0800
Subject: Input: libps2 - support retransmission of command data

The devices are allowed to respond to either command byte or command
parameter with a NAK (0xfe), and the host is supposed to resend the
"correct" byte. The device then will either respond with ACK or ERR (0xfc).
Let's teach libps2 to handle the NAK responses properly, so that individual
drivers do not need to handle them.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
---
 drivers/input/serio/libps2.c | 103 +++++++++++++++++++++++++++++--------------
 1 file changed, 71 insertions(+), 32 deletions(-)

(limited to 'drivers/input/serio')

diff --git a/drivers/input/serio/libps2.c b/drivers/input/serio/libps2.c
index 82befae4dab0..f05c407b31f3 100644
--- a/drivers/input/serio/libps2.c
+++ b/drivers/input/serio/libps2.c
@@ -26,35 +26,63 @@ MODULE_AUTHOR("Dmitry Torokhov <dtor@mail.ru>");
 MODULE_DESCRIPTION("PS/2 driver library");
 MODULE_LICENSE("GPL");
 
-static int ps2_do_sendbyte(struct ps2dev *ps2dev, u8 byte, unsigned int timeout)
+static int ps2_do_sendbyte(struct ps2dev *ps2dev, u8 byte,
+			   unsigned int timeout, unsigned int max_attempts)
+	__releases(&ps2dev->serio->lock) __acquires(&ps2dev->serio->lock)
 {
+	int attempt = 0;
 	int error;
 
-	serio_pause_rx(ps2dev->serio);
-	ps2dev->nak = 1;
-	ps2dev->flags |= PS2_FLAG_ACK;
-	serio_continue_rx(ps2dev->serio);
+	lockdep_assert_held(&ps2dev->serio->lock);
 
-	error = serio_write(ps2dev->serio, byte);
-	if (error)
-		dev_dbg(&ps2dev->serio->dev,
-			"failed to write %#02x: %d\n", byte, error);
-	else
-		wait_event_timeout(ps2dev->wait,
-				   !(ps2dev->flags & PS2_FLAG_ACK),
-				   msecs_to_jiffies(timeout));
+	do {
+		ps2dev->nak = 1;
+		ps2dev->flags |= PS2_FLAG_ACK;
+
+		serio_continue_rx(ps2dev->serio);
+
+		error = serio_write(ps2dev->serio, byte);
+		if (error)
+			dev_dbg(&ps2dev->serio->dev,
+				"failed to write %#02x: %d\n", byte, error);
+		else
+			wait_event_timeout(ps2dev->wait,
+					   !(ps2dev->flags & PS2_FLAG_ACK),
+					   msecs_to_jiffies(timeout));
+
+		serio_pause_rx(ps2dev->serio);
+	} while (ps2dev->nak == PS2_RET_NAK && ++attempt < max_attempts);
 
-	serio_pause_rx(ps2dev->serio);
 	ps2dev->flags &= ~PS2_FLAG_ACK;
-	serio_continue_rx(ps2dev->serio);
 
-	return -ps2dev->nak;
+	if (!error) {
+		switch (ps2dev->nak) {
+		case 0:
+			break;
+		case PS2_RET_NAK:
+			error = -EAGAIN;
+			break;
+		case PS2_RET_ERR:
+			error = -EPROTO;
+			break;
+		default:
+			error = -EIO;
+			break;
+		}
+	}
+
+	if (error || attempt > 1)
+		dev_dbg(&ps2dev->serio->dev,
+			"%02x - %d (%x), attempt %d\n",
+			byte, error, ps2dev->nak, attempt);
+
+	return error;
 }
 
 /*
  * ps2_sendbyte() sends a byte to the device and waits for acknowledge.
- * It doesn't handle retransmission, though it could - because if there
- * is a need for retransmissions device has to be replaced anyway.
+ * It doesn't handle retransmission, the caller is expected to handle
+ * it when needed.
  *
  * ps2_sendbyte() can only be called from a process context.
  */
@@ -63,9 +91,13 @@ int ps2_sendbyte(struct ps2dev *ps2dev, u8 byte, unsigned int timeout)
 {
 	int retval;
 
-	retval = ps2_do_sendbyte(ps2dev, byte, timeout);
+	serio_pause_rx(ps2dev->serio);
+
+	retval = ps2_do_sendbyte(ps2dev, byte, timeout, 1);
 	dev_dbg(&ps2dev->serio->dev, "%02x - %x\n", byte, ps2dev->nak);
 
+	serio_continue_rx(ps2dev->serio);
+
 	return retval;
 }
 EXPORT_SYMBOL(ps2_sendbyte);
@@ -200,48 +232,48 @@ int __ps2_command(struct ps2dev *ps2dev, u8 *param, unsigned int command)
 	unsigned int timeout;
 	unsigned int send = (command >> 12) & 0xf;
 	unsigned int receive = (command >> 8) & 0xf;
-	int rc = -1;
+	int rc;
 	int i;
 	u8 send_param[16];
 
 	if (receive > sizeof(ps2dev->cmdbuf)) {
 		WARN_ON(1);
-		return -1;
+		return -EINVAL;
 	}
 
 	if (send && !param) {
 		WARN_ON(1);
-		return -1;
+		return -EINVAL;
 	}
 
 	memcpy(send_param, param, send);
 
 	serio_pause_rx(ps2dev->serio);
+
 	ps2dev->flags = command == PS2_CMD_GETID ? PS2_FLAG_WAITID : 0;
 	ps2dev->cmdcnt = receive;
 	if (receive && param)
 		for (i = 0; i < receive; i++)
 			ps2dev->cmdbuf[(receive - 1) - i] = param[i];
-	serio_continue_rx(ps2dev->serio);
 
 	/*
 	 * Some devices (Synaptics) peform the reset before
 	 * ACKing the reset command, and so it can take a long
 	 * time before the ACK arrives.
 	 */
-	if (ps2_do_sendbyte(ps2dev, command & 0xff,
-			    command == PS2_CMD_RESET_BAT ? 1000 : 200)) {
-		serio_pause_rx(ps2dev->serio);
+	rc = ps2_do_sendbyte(ps2dev, command & 0xff,
+			     command == PS2_CMD_RESET_BAT ? 1000 : 200, 2);
+	if (rc)
 		goto out_reset_flags;
-	}
 
 	for (i = 0; i < send; i++) {
-		if (ps2_do_sendbyte(ps2dev, param[i], 200)) {
-			serio_pause_rx(ps2dev->serio);
+		rc = ps2_do_sendbyte(ps2dev, param[i], 200, 2);
+		if (rc)
 			goto out_reset_flags;
-		}
 	}
 
+	serio_continue_rx(ps2dev->serio);
+
 	/*
 	 * The reset command takes a long time to execute.
 	 */
@@ -263,8 +295,11 @@ int __ps2_command(struct ps2dev *ps2dev, u8 *param, unsigned int command)
 		for (i = 0; i < receive; i++)
 			param[i] = ps2dev->cmdbuf[(receive - 1) - i];
 
-	if (ps2dev->cmdcnt && (command != PS2_CMD_RESET_BAT || ps2dev->cmdcnt != 1))
+	if (ps2dev->cmdcnt &&
+	    (command != PS2_CMD_RESET_BAT || ps2dev->cmdcnt != 1)) {
+		rc = -EPROTO;
 		goto out_reset_flags;
+	}
 
 	rc = 0;
 
@@ -278,7 +313,11 @@ int __ps2_command(struct ps2dev *ps2dev, u8 *param, unsigned int command)
 		ps2dev->nak, ps2dev->flags,
 		receive, param ?: send_param);
 
-	return rc;
+	/*
+	 * ps_command() handles resends itself, so do not leak -EAGAIN
+	 * to the callers.
+	 */
+	return rc != -EAGAIN ? rc : -EPROTO;
 }
 EXPORT_SYMBOL(__ps2_command);
 
-- 
cgit v1.2.3


From 29acc42e8e10a4721757af9ed8aec569d30ce39b Mon Sep 17 00:00:00 2001
From: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Date: Wed, 17 Jan 2018 12:00:24 -0800
Subject: Input: libps2 - relax command byte ACK handling

When we probe PS/2 devices we first issue "Get ID" command and only if we
receive what we consider a valid keyboard or mouse ID we disable the device
and continue with protocol detection. That means that the device may be
transmitting motion or keystroke data, while we expect ACK response.

Instead of signaling failure if we see anything but ACK/NAK let's ignore
"garbage" response until we see ACK for the command byte (first byte). The
checks for subsequent ACKs of command parameters will continue be strict.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
---
 drivers/input/serio/libps2.c | 25 ++++++++++++++++++++++---
 include/linux/libps2.h       |  1 +
 2 files changed, 23 insertions(+), 3 deletions(-)

(limited to 'drivers/input/serio')

diff --git a/drivers/input/serio/libps2.c b/drivers/input/serio/libps2.c
index f05c407b31f3..e6a07e68d1ff 100644
--- a/drivers/input/serio/libps2.c
+++ b/drivers/input/serio/libps2.c
@@ -256,16 +256,23 @@ int __ps2_command(struct ps2dev *ps2dev, u8 *param, unsigned int command)
 		for (i = 0; i < receive; i++)
 			ps2dev->cmdbuf[(receive - 1) - i] = param[i];
 
+	/* Signal that we are sending the command byte */
+	ps2dev->flags |= PS2_FLAG_ACK_CMD;
+
 	/*
 	 * Some devices (Synaptics) peform the reset before
 	 * ACKing the reset command, and so it can take a long
 	 * time before the ACK arrives.
 	 */
-	rc = ps2_do_sendbyte(ps2dev, command & 0xff,
-			     command == PS2_CMD_RESET_BAT ? 1000 : 200, 2);
+	timeout = command == PS2_CMD_RESET_BAT ? 1000 : 200;
+
+	rc = ps2_do_sendbyte(ps2dev, command & 0xff, timeout, 2);
 	if (rc)
 		goto out_reset_flags;
 
+	/* Now we are sending command parameters, if any */
+	ps2dev->flags &= ~PS2_FLAG_ACK_CMD;
+
 	for (i = 0; i < send; i++) {
 		rc = ps2_do_sendbyte(ps2dev, param[i], 200, 2);
 		if (rc)
@@ -416,7 +423,19 @@ bool ps2_handle_ack(struct ps2dev *ps2dev, u8 data)
 		}
 		/* Fall through */
 	default:
-		return false;
+		/*
+		 * Do not signal errors if we get unexpected reply while
+		 * waiting for an ACK to the initial (first) command byte:
+		 * the device might not be quiesced yet and continue
+		 * delivering data.
+		 * Note that we reset PS2_FLAG_WAITID flag, so the workaround
+		 * for mice not acknowledging the Get ID command only triggers
+		 * on the 1st byte; if device spews data we really want to see
+		 * a real ACK from it.
+		 */
+		dev_dbg(&ps2dev->serio->dev, "unexpected %#02x\n", data);
+		ps2dev->flags &= ~PS2_FLAG_WAITID;
+		return ps2dev->flags & PS2_FLAG_ACK_CMD;
 	}
 
 	if (!ps2dev->nak) {
diff --git a/include/linux/libps2.h b/include/linux/libps2.h
index 3c69cd796f48..5f18fe02ae37 100644
--- a/include/linux/libps2.h
+++ b/include/linux/libps2.h
@@ -31,6 +31,7 @@
 #define PS2_FLAG_CMD1		BIT(2)	/* Waiting for the first byte of command response */
 #define PS2_FLAG_WAITID		BIT(3)	/* Command executing is GET ID */
 #define PS2_FLAG_NAK		BIT(4)	/* Last transmission was NAKed */
+#define PS2_FLAG_ACK_CMD	BIT(5)	/* Waiting to ACK the command (first) byte */
 
 struct ps2dev {
 	struct serio *serio;
-- 
cgit v1.2.3