[PATCH 2/8] android_pipe: don't be clever with #define offsets

From: Jin Qian
Date: Tue Nov 24 2015 - 20:11:03 EST


From: Alex BennÃe <alex.bennee@xxxxxxxxxx>

You just make it harder to figure out when commands are being used.

Signed-off-by: Alex BennÃe <alex.bennee@xxxxxxxxxx>
(cherry picked from commit b765d478f67a2f6cb43c40a99114ea5ff1bcff97)
Signed-off-by: Jin Qian <jinqian@xxxxxxxxxxx>
---
drivers/platform/goldfish/goldfish_pipe.c | 16 +++++-----------
1 file changed, 5 insertions(+), 11 deletions(-)

diff --git a/drivers/platform/goldfish/goldfish_pipe.c b/drivers/platform/goldfish/goldfish_pipe.c
index e7a29e2..0fb3a34 100644
--- a/drivers/platform/goldfish/goldfish_pipe.c
+++ b/drivers/platform/goldfish/goldfish_pipe.c
@@ -90,12 +90,6 @@
#define CMD_WRITE_BUFFER 4 /* send a user buffer to the emulator */
#define CMD_WAKE_ON_WRITE 5 /* tell the emulator to wake us when writing
is possible */
-
-/* The following commands are related to read operations, they must be
- * listed in the same order than the corresponding write ones, since we
- * will use (CMD_READ_BUFFER - CMD_WRITE_BUFFER) as a special offset
- * in goldfish_pipe_read_write() below.
- */
#define CMD_READ_BUFFER 6 /* receive a user buffer from the emulator */
#define CMD_WAKE_ON_READ 7 /* tell the emulator to wake us when reading
* is possible */
@@ -272,8 +266,6 @@ static ssize_t goldfish_pipe_read_write(struct file *filp, char __user *buffer,
unsigned long irq_flags;
struct goldfish_pipe *pipe = filp->private_data;
struct goldfish_pipe_dev *dev = pipe->dev;
- const int cmd_offset = is_write ? 0
- : (CMD_READ_BUFFER - CMD_WRITE_BUFFER);
unsigned long address, address_end;
int ret = 0;

@@ -325,7 +317,8 @@ static ssize_t goldfish_pipe_read_write(struct file *filp, char __user *buffer,

/* Now, try to transfer the bytes in the current page */
spin_lock_irqsave(&dev->lock, irq_flags);
- if (access_with_param(dev, CMD_WRITE_BUFFER + cmd_offset,
+ if (access_with_param(dev,
+ is_write ? CMD_WRITE_BUFFER : CMD_READ_BUFFER,
address, avail, pipe, &status)) {
gf_write_ptr(pipe, dev->base + PIPE_REG_CHANNEL,
dev->base + PIPE_REG_CHANNEL_HIGH);
@@ -333,7 +326,7 @@ static ssize_t goldfish_pipe_read_write(struct file *filp, char __user *buffer,
gf_write_ptr((void *)address,
dev->base + PIPE_REG_ADDRESS,
dev->base + PIPE_REG_ADDRESS_HIGH);
- writel(CMD_WRITE_BUFFER + cmd_offset,
+ writel(is_write ? CMD_WRITE_BUFFER : CMD_READ_BUFFER,
dev->base + PIPE_REG_COMMAND);
status = readl(dev->base + PIPE_REG_STATUS);
}
@@ -370,7 +363,8 @@ static ssize_t goldfish_pipe_read_write(struct file *filp, char __user *buffer,
set_bit(wakeBit, &pipe->flags);

/* Tell the emulator we're going to wait for a wake event */
- goldfish_cmd(pipe, CMD_WAKE_ON_WRITE + cmd_offset);
+ goldfish_cmd(pipe,
+ is_write ? CMD_WAKE_ON_WRITE : CMD_WAKE_ON_READ);

/* Unlock the pipe, then wait for the wake signal */
mutex_unlock(&pipe->lock);
--
2.6.0.rc2.230.g3dd15c0

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