Re: [PATCH v4 3/3] thermal: zx2967: add thermal driver for ZTE's zx2967 family

From: Eduardo Valentin
Date: Tue Jan 17 2017 - 00:26:33 EST


Hello,

On Fri, Jan 13, 2017 at 06:46:58PM +0800, Baoyou Xie wrote:
> This patch adds thermal driver for ZTE's zx2967 family.

Please consider the comments I sent on your v3. They still apply here.

and also the following:

>
> Signed-off-by: Baoyou Xie <baoyou.xie@xxxxxxxxxx>


<cut>

> +static int zx2967_thermal_get_temp(void *data, int *temp)
> +{
> + void __iomem *regs;
> + struct zx2967_thermal_sensor *sensor = data;
> + struct zx2967_thermal_priv *priv = sensor->priv;
> + unsigned long timeout = jiffies + msecs_to_jiffies(100);
> + u32 val, sel_id;
> +
> + regs = priv->regs;
> + mutex_lock(&priv->lock);
> +
> + writel_relaxed(0, regs + ZX2967_THERMAL_POWER_MODE);
> + writel_relaxed(2, regs + ZX2967_THERMAL_DCF);
> +
> + val = readl_relaxed(regs + ZX2967_THERMAL_SEL);
> + val &= ~ZX2967_THERMAL_ID_MASK;
> + sel_id = sensor->id ? ZX2967_THERMAL_ID0 : ZX2967_THERMAL_ID1;
> + val |= sel_id;
> + writel_relaxed(val, regs + ZX2967_THERMAL_SEL);
> +
> + usleep_range(100, 300);
> + val = readl_relaxed(regs + ZX2967_THERMAL_CTRL);
> + while (!(val & ZX2967_THERMAL_READY)) {
> + if (time_after(jiffies, timeout)) {
> + dev_err(priv->dev, "Thermal sensor %d data timeout\n",
> + sensor->id);
> + mutex_unlock(&priv->lock);
> + return -ETIMEDOUT;
> + }
> + val = readl_relaxed(regs + ZX2967_THERMAL_CTRL);

should you usleep_range() in between loops iterations?

> + }
> +
> + writel_relaxed(3, regs + ZX2967_THERMAL_DCF);
> + val = readl_relaxed(regs + ZX2967_THERMAL_CTRL)
> + & ZX2967_THERMAL_TEMP_MASK;
> + writel_relaxed(1, regs + ZX2967_THERMAL_POWER_MODE);
> +
> + /*
> + * Calculate temperature
> + * 922 initial value of calibration cure
> + * 1.951 slope of calibration cure
> + */
> + *temp = DIV_ROUND_CLOSEST((val - 922) * 1000, 1951);
> +
> + mutex_unlock(&priv->lock);
> +
> + return 0;
> +}
> +
> +static struct thermal_zone_of_device_ops zx2967_of_thermal_ops = {
> + .get_temp = zx2967_thermal_get_temp,
> +};
> +
> +static int zx2967_thermal_probe(struct platform_device *pdev)
> +{
> + struct zx2967_thermal_priv *priv;
> + struct resource *res;
> + int ret, i;
> +
> + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
> + if (!priv)
> + return -ENOMEM;
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + priv->regs = devm_ioremap_resource(&pdev->dev, res);
> + if (IS_ERR(priv->regs))
> + return PTR_ERR(priv->regs);
> +
> + priv->clk_gate = devm_clk_get(&pdev->dev, "gate");
> + if (IS_ERR(priv->clk_gate)) {
> + ret = PTR_ERR(priv->clk_gate);
> + dev_err(&pdev->dev, "failed to get clock gate: %d\n", ret);
> + return ret;
> + }
> +
> + ret = clk_prepare_enable(priv->clk_gate);
> + if (ret) {
> + dev_err(&pdev->dev, "failed to enable converter clock: %d\n",
> + ret);
> + return ret;
> + }
> +
> + priv->pclk = devm_clk_get(&pdev->dev, "pclk");
> + if (IS_ERR(priv->pclk)) {
> + ret = PTR_ERR(priv->pclk);
> + dev_err(&pdev->dev, "failed to get apb clock: %d\n", ret);
> + return ret;
> + }
> +
> + ret = clk_prepare_enable(priv->pclk);
> + if (ret) {
> + clk_disable_unprepare(priv->clk_gate);
> + dev_err(&pdev->dev, "failed to enable converter clock: %d\n",
> + ret);
> + return ret;
> + }
> +
> + mutex_init(&priv->lock);
> + for (i = 0; i < NUM_SENSORS; i++) {
> + struct zx2967_thermal_sensor *sensor = &priv->sensors[i];
> +
> + sensor->priv = priv;
> + sensor->id = i;
> + sensor->tzd = thermal_zone_of_sensor_register(&pdev->dev,
> + i, sensor, &zx2967_of_thermal_ops);
> + if (IS_ERR(sensor->tzd)) {
> + ret = PTR_ERR(sensor->tzd);
> + dev_err(&pdev->dev, "failed to register sensor %d: %d\n",
> + i, ret);
> + goto remove_ts;
> + }
> + }
> + priv->dev = &pdev->dev;
> + platform_set_drvdata(pdev, priv);
> +
> + return 0;
> +
> +remove_ts:
> + clk_disable_unprepare(priv->clk_gate);
> + clk_disable_unprepare(priv->pclk);
> + for (i--; i >= 0; i--)
> + thermal_zone_of_sensor_unregister(&pdev->dev,
> + priv->sensors[i].tzd);
> +
> + return ret;
> +}
> +
> +static int zx2967_thermal_exit(struct platform_device *pdev)
> +{
> + struct zx2967_thermal_priv *priv = platform_get_drvdata(pdev);
> + int i;
> +
> + for (i = 0; i < NUM_SENSORS; i++) {
> + struct zx2967_thermal_sensor *sensor = &priv->sensors[i];
> +
> + thermal_zone_of_sensor_unregister(&pdev->dev, sensor->tzd);
> + }
> + clk_disable_unprepare(priv->pclk);
> + clk_disable_unprepare(priv->clk_gate);
> +
> + return 0;
> +}
> +
> +static const struct of_device_id zx2967_thermal_id_table[] = {
> + { .compatible = "zte,zx296718-thermal" },
> + {}
> +};
> +MODULE_DEVICE_TABLE(of, zx2967_thermal_id_table);
> +
> +static SIMPLE_DEV_PM_OPS(zx2967_thermal_pm_ops,
> + zx2967_thermal_suspend, zx2967_thermal_resume);
> +
> +static struct platform_driver zx2967_thermal_driver = {
> + .probe = zx2967_thermal_probe,
> + .remove = zx2967_thermal_exit,
> + .driver = {
> + .name = "zx2967_thermal",
> + .of_match_table = zx2967_thermal_id_table,
> + .pm = &zx2967_thermal_pm_ops,
> + },
> +};
> +module_platform_driver(zx2967_thermal_driver);
> +
> +MODULE_AUTHOR("Baoyou Xie <baoyou.xie@xxxxxxxxxx>");
> +MODULE_DESCRIPTION("ZTE zx2967 thermal driver");
> +MODULE_LICENSE("GPL");

GPLv2?

> --
> 2.7.4
>