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authorMathieu Poirier <mathieu.poirier@linaro.org>2016-05-03 20:33:46 +0300
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2016-05-04 00:59:30 +0300
commitb1789b793eb4627928f55a6acea8da7c25e5c6b4 (patch)
tree63d4327bdd58e2094892ea2c3f367a8d02e50380 /drivers/hwtracing
parent358f42184e97f9a216b927a5a744597b98e0eee1 (diff)
downloadlinux-b1789b793eb4627928f55a6acea8da7c25e5c6b4.tar.xz
coresight: tmc: re-implementing tmc_read_prepare/unprepare() functions
In their current implementation the tmc_read_prepare/unprepare() are a lump of if/else that is difficult to read. This patch is alleviating that by using a switch statement. The latter also allows for a better control on the error path. Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/hwtracing')
-rw-r--r--drivers/hwtracing/coresight/coresight-tmc.c56
1 files changed, 36 insertions, 20 deletions
diff --git a/drivers/hwtracing/coresight/coresight-tmc.c b/drivers/hwtracing/coresight/coresight-tmc.c
index 66fa7736d12f..d211aeec49f8 100644
--- a/drivers/hwtracing/coresight/coresight-tmc.c
+++ b/drivers/hwtracing/coresight/coresight-tmc.c
@@ -431,7 +431,7 @@ static const struct coresight_ops tmc_etf_cs_ops = {
static int tmc_read_prepare(struct tmc_drvdata *drvdata)
{
- int ret;
+ int ret = 0;
unsigned long flags;
enum tmc_mode mode;
@@ -439,25 +439,31 @@ static int tmc_read_prepare(struct tmc_drvdata *drvdata)
if (!drvdata->enable)
goto out;
- if (drvdata->config_type == TMC_CONFIG_TYPE_ETB) {
+ switch (drvdata->config_type) {
+ case TMC_CONFIG_TYPE_ETB:
tmc_etb_disable_hw(drvdata);
- } else if (drvdata->config_type == TMC_CONFIG_TYPE_ETR) {
- tmc_etr_disable_hw(drvdata);
- } else {
+ break;
+ case TMC_CONFIG_TYPE_ETF:
+ /* There is no point in reading a TMC in HW FIFO mode */
mode = readl_relaxed(drvdata->base + TMC_MODE);
- if (mode == TMC_MODE_CIRCULAR_BUFFER) {
- tmc_etb_disable_hw(drvdata);
- } else {
- ret = -ENODEV;
+ if (mode != TMC_MODE_CIRCULAR_BUFFER) {
+ ret = -EINVAL;
goto err;
}
+
+ tmc_etb_disable_hw(drvdata);
+ break;
+ case TMC_CONFIG_TYPE_ETR:
+ tmc_etr_disable_hw(drvdata);
+ break;
+ default:
+ ret = -EINVAL;
+ goto err;
}
+
out:
drvdata->reading = true;
- spin_unlock_irqrestore(&drvdata->spinlock, flags);
-
dev_info(drvdata->dev, "TMC read start\n");
- return 0;
err:
spin_unlock_irqrestore(&drvdata->spinlock, flags);
return ret;
@@ -472,20 +478,30 @@ static void tmc_read_unprepare(struct tmc_drvdata *drvdata)
if (!drvdata->enable)
goto out;
- if (drvdata->config_type == TMC_CONFIG_TYPE_ETB) {
+ switch (drvdata->config_type) {
+ case TMC_CONFIG_TYPE_ETB:
tmc_etb_enable_hw(drvdata);
- } else if (drvdata->config_type == TMC_CONFIG_TYPE_ETR) {
- tmc_etr_enable_hw(drvdata);
- } else {
+ break;
+ case TMC_CONFIG_TYPE_ETF:
+ /* Make sure we don't re-enable a TMC in HW FIFO mode */
mode = readl_relaxed(drvdata->base + TMC_MODE);
- if (mode == TMC_MODE_CIRCULAR_BUFFER)
- tmc_etb_enable_hw(drvdata);
+ if (mode != TMC_MODE_CIRCULAR_BUFFER)
+ goto err;
+
+ tmc_etb_enable_hw(drvdata);
+ break;
+ case TMC_CONFIG_TYPE_ETR:
+ tmc_etr_disable_hw(drvdata);
+ break;
+ default:
+ goto err;
}
+
out:
drvdata->reading = false;
- spin_unlock_irqrestore(&drvdata->spinlock, flags);
-
dev_info(drvdata->dev, "TMC read end\n");
+err:
+ spin_unlock_irqrestore(&drvdata->spinlock, flags);
}
static int tmc_open(struct inode *inode, struct file *file)