4.9-stable review patch. If anyone has any objections, please let me know.
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From: Nick Desaulniers nick.desaulniers@gmail.com
commit dae1a432ab1fe79ae53129ededeaece35a2dc14d upstream.
Clang warns:
drivers/input/mousedev.c:653:63: error: implicit conversion from 'int' to 'signed char' changes value from 200 to -56 [-Wconstant-conversion] client->ps2[1] = 0x60; client->ps2[2] = 3; client->ps2[3] = 200; ~ ^~~ As the PS2 data is really a stream of bytes, let's switch to using u8 type for it, which silences this warning.
Signed-off-by: Nick Desaulniers nick.desaulniers@gmail.com Signed-off-by: Dmitry Torokhov dmitry.torokhov@gmail.com Cc: Nathan Chancellor natechancellor@gmail.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/input/mousedev.c | 62 +++++++++++++++++++++++++---------------------- 1 file changed, 34 insertions(+), 28 deletions(-)
--- a/drivers/input/mousedev.c +++ b/drivers/input/mousedev.c @@ -15,6 +15,7 @@ #define MOUSEDEV_MINORS 31 #define MOUSEDEV_MIX 63
+#include <linux/bitops.h> #include <linux/sched.h> #include <linux/slab.h> #include <linux/poll.h> @@ -103,7 +104,7 @@ struct mousedev_client { spinlock_t packet_lock; int pos_x, pos_y;
- signed char ps2[6]; + u8 ps2[6]; unsigned char ready, buffer, bufsiz; unsigned char imexseq, impsseq; enum mousedev_emul mode; @@ -291,11 +292,10 @@ static void mousedev_notify_readers(stru }
client->pos_x += packet->dx; - client->pos_x = client->pos_x < 0 ? - 0 : (client->pos_x >= xres ? xres : client->pos_x); + client->pos_x = clamp_val(client->pos_x, 0, xres); + client->pos_y += packet->dy; - client->pos_y = client->pos_y < 0 ? - 0 : (client->pos_y >= yres ? yres : client->pos_y); + client->pos_y = clamp_val(client->pos_y, 0, yres);
p->dx += packet->dx; p->dy += packet->dy; @@ -571,44 +571,50 @@ static int mousedev_open(struct inode *i return error; }
-static inline int mousedev_limit_delta(int delta, int limit) -{ - return delta > limit ? limit : (delta < -limit ? -limit : delta); -} - -static void mousedev_packet(struct mousedev_client *client, - signed char *ps2_data) +static void mousedev_packet(struct mousedev_client *client, u8 *ps2_data) { struct mousedev_motion *p = &client->packets[client->tail]; + s8 dx, dy, dz; + + dx = clamp_val(p->dx, -127, 127); + p->dx -= dx; + + dy = clamp_val(p->dy, -127, 127); + p->dy -= dy;
- ps2_data[0] = 0x08 | - ((p->dx < 0) << 4) | ((p->dy < 0) << 5) | (p->buttons & 0x07); - ps2_data[1] = mousedev_limit_delta(p->dx, 127); - ps2_data[2] = mousedev_limit_delta(p->dy, 127); - p->dx -= ps2_data[1]; - p->dy -= ps2_data[2]; + ps2_data[0] = BIT(3); + ps2_data[0] |= ((dx & BIT(7)) >> 3) | ((dy & BIT(7)) >> 2); + ps2_data[0] |= p->buttons & 0x07; + ps2_data[1] = dx; + ps2_data[2] = dy;
switch (client->mode) { case MOUSEDEV_EMUL_EXPS: - ps2_data[3] = mousedev_limit_delta(p->dz, 7); - p->dz -= ps2_data[3]; - ps2_data[3] = (ps2_data[3] & 0x0f) | ((p->buttons & 0x18) << 1); + dz = clamp_val(p->dz, -7, 7); + p->dz -= dz; + + ps2_data[3] = (dz & 0x0f) | ((p->buttons & 0x18) << 1); client->bufsiz = 4; break;
case MOUSEDEV_EMUL_IMPS: - ps2_data[0] |= - ((p->buttons & 0x10) >> 3) | ((p->buttons & 0x08) >> 1); - ps2_data[3] = mousedev_limit_delta(p->dz, 127); - p->dz -= ps2_data[3]; + dz = clamp_val(p->dz, -127, 127); + p->dz -= dz; + + ps2_data[0] |= ((p->buttons & 0x10) >> 3) | + ((p->buttons & 0x08) >> 1); + ps2_data[3] = dz; + client->bufsiz = 4; break;
case MOUSEDEV_EMUL_PS2: default: - ps2_data[0] |= - ((p->buttons & 0x10) >> 3) | ((p->buttons & 0x08) >> 1); p->dz = 0; + + ps2_data[0] |= ((p->buttons & 0x10) >> 3) | + ((p->buttons & 0x08) >> 1); + client->bufsiz = 3; break; } @@ -714,7 +720,7 @@ static ssize_t mousedev_read(struct file { struct mousedev_client *client = file->private_data; struct mousedev *mousedev = client->mousedev; - signed char data[sizeof(client->ps2)]; + u8 data[sizeof(client->ps2)]; int retval = 0;
if (!client->ready && !client->buffer && mousedev->exist &&