From b1789b793eb4627928f55a6acea8da7c25e5c6b4 Mon Sep 17 00:00:00 2001 From: Mathieu Poirier Date: Tue, 3 May 2016 11:33:46 -0600 Subject: [PATCH] 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 Reviewed-by: Suzuki K Poulose Signed-off-by: Greg Kroah-Hartman --- drivers/hwtracing/coresight/coresight-tmc.c | 56 +++++++++++++-------- 1 file 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) -- 2.20.1