Message ID | 20241209-imx91tmu-v1-2-7859c5387f31@nxp.com (mailing list archive) |
---|---|
State | Superseded |
Headers | show |
Series | thermal: imx91: Add support for i.MX91 thermal monitoring unit | expand |
Hi, On 24-12-09, Frank Li wrote: > From: Pengfei Li <pengfei.li_1@nxp.com> > > Introduce support for the i.MX91 thermal monitoring unit, which features a > single sensor for the CPU. The register layout differs from other chips, > necessitating the creation of a dedicated file for this. > > Signed-off-by: Pengfei Li <pengfei.li_1@nxp.com> > Signed-off-by: Peng Fan <peng.fan@nxp.com> > Signed-off-by: Frank Li <Frank.Li@nxp.com> > --- > drivers/thermal/Kconfig | 10 ++ > drivers/thermal/Makefile | 1 + > drivers/thermal/imx91_thermal.c | 281 ++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 292 insertions(+) > > diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig > index d3f9686e26e71..da403ed86aeb1 100644 > --- a/drivers/thermal/Kconfig > +++ b/drivers/thermal/Kconfig > @@ -296,6 +296,16 @@ config IMX8MM_THERMAL > cpufreq is used as the cooling device to throttle CPUs when the passive > trip is crossed. > > +config IMX91_THERMAL > + tristate "Temperature sensor driver for NXP i.MX91 SoC" > + depends on ARCH_MXC || COMPILE_TEST > + depends on OF > + help > + Support for Temperature sensor found on NXP i.MX91 SoC. > + It supports one critical trip point and one passive trip point. The > + cpufreq is used as the cooling device to throttle CPUs when the passive > + trip is crossed. > + > config K3_THERMAL > tristate "Texas Instruments K3 thermal support" > depends on ARCH_K3 || COMPILE_TEST > diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile > index 9abf43a74f2bb..08da241e6a598 100644 > --- a/drivers/thermal/Makefile > +++ b/drivers/thermal/Makefile > @@ -50,6 +50,7 @@ obj-$(CONFIG_ARMADA_THERMAL) += armada_thermal.o > obj-$(CONFIG_IMX_THERMAL) += imx_thermal.o > obj-$(CONFIG_IMX_SC_THERMAL) += imx_sc_thermal.o > obj-$(CONFIG_IMX8MM_THERMAL) += imx8mm_thermal.o > +obj-$(CONFIG_IMX91_THERMAL) += imx91_thermal.o > obj-$(CONFIG_MAX77620_THERMAL) += max77620_thermal.o > obj-$(CONFIG_QORIQ_THERMAL) += qoriq_thermal.o > obj-$(CONFIG_DA9062_THERMAL) += da9062-thermal.o > diff --git a/drivers/thermal/imx91_thermal.c b/drivers/thermal/imx91_thermal.c > new file mode 100644 > index 0000000000000..19c4dafe9c7a9 > --- /dev/null > +++ b/drivers/thermal/imx91_thermal.c > @@ -0,0 +1,281 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Copyright 2024 NXP. > + */ > + > +#include <linux/bitfield.h> > +#include <linux/clk.h> > +#include <linux/err.h> > +#include <linux/iopoll.h> > +#include <linux/nvmem-consumer.h> > +#include <linux/module.h> > +#include <linux/of.h> > +#include <linux/of_device.h> > +#include <linux/platform_device.h> > +#include <linux/thermal.h> > + > +#define CTRL0 0x0 > + > +#define STAT0 0x10 > +#define STAT0_DRDY0_IF_MASK BIT(16) > + > +#define DATA0 0x20 > +#define DATA_INT_MASK GENMASK(14, 7) > +#define DATA_FRAC_MASK GENMASK(6, 0) > + > +#define THR_CTRL01 0x30 > +#define THR_CTRL23 0x40 > + > +#define CTRL1 0x200 > +#define CTRL1_SET 0x204 > +#define CTRL1_CLR 0x208 > +#define CTRL1_EN BIT(31) > +#define CTRL1_START BIT(30) > +#define CTRL1_STOP BIT(29) > +#define CTRL1_RES_MASK GENMASK(19, 18) > +#define CTRL1_MEAS_MODE_MASK GENMASK(25, 24) > + > +#define PERIOD_CTRL 0x270 > +#define MEAS_FREQ_MASK GENMASK(23, 0) > + > +#define REF_DIV 0x280 > +#define DIV_EN BIT(31) > +#define DIV_MASK GENMASK(23, 16) > + > +#define PUD_ST_CTRL 0x2B0 > +#define PUDL_MASK GENMASK(23, 16) > + > +#define TRIM1 0x2E0 > +#define TRIM2 0x2F0 > + > +#define TMU_TEMP_LOW_LIMIT -40000 > +#define TMU_TEMP_HIGH_LIMIT 125000 > + > +#define DEFAULT_TRIM1_CONFIG 0xB561BC2DU > +#define DEFAULT_TRIM2_CONFIG 0x65D4U please align the defines and use lower-case for the hex values. > +struct tmu_sensor { > + struct imx91_tmu *priv; > + struct thermal_zone_device *tzd; > +}; This can be part of imx91_tmu right? > +struct imx91_tmu { > + void __iomem *base; > + struct clk *clk; > + struct device *dev; > + struct tmu_sensor sensors; > +}; > + > +static void imx91_tmu_start(struct imx91_tmu *tmu, bool start) > +{ > + if (start) > + writel_relaxed(CTRL1_START, tmu->base + CTRL1_SET); > + else > + writel_relaxed(CTRL1_STOP, tmu->base + CTRL1_SET); Nit: unsigned int val = start ? CTRL1_START : CTRL1_STOP; writel_relaxed(val, tmu->base + CTRL1_SET); Aside the nit, why do you use *_relaxed() accessors in you whole code? Is the order not strictly required? > +} > + > +static void imx91_tmu_enable(struct imx91_tmu *tmu, bool enable) > +{ > + if (enable) > + writel_relaxed(CTRL1_EN, tmu->base + CTRL1_SET); > + else > + writel_relaxed(CTRL1_EN, tmu->base + CTRL1_CLR); Same here: unsigned int reg = enable ? CTRL1_SET : CTRL1_CLR; writel_relaxed(CTRL1_EN, tmu->base + reg); > +} > + > +static int imx91_tmu_get_temp(struct thermal_zone_device *tz, int *temp) > +{ > + struct tmu_sensor *sensor = thermal_zone_device_priv(tz); > + struct imx91_tmu *tmu = sensor->priv; With tmu_sensor merged into imx91_tmu you don't need this reverse pointer logic. > + int val; > + int ret; > + > + ret = readl_relaxed_poll_timeout(tmu->base + STAT0, val, > + val & STAT0_DRDY0_IF_MASK, 1000, > + 40000); > + if (ret) > + return -EAGAIN; > + > + val = readl_relaxed(tmu->base + DATA0) & 0xffffU; ^ Please use a MASK define for it, also no need to use the U suffix. Also according the TRM 58.3.4 this doesn't seem right. According the TRM this is a s16 (two's-complement) value. You won't get negative values if store it within a int. > + *temp = val * 1000L / 64L; ^ ^ You don't need to specify the type here explicit since all params would be converted to int and no overflow happens. > + if (*temp < TMU_TEMP_LOW_LIMIT || *temp > TMU_TEMP_HIGH_LIMIT) > + return -EAGAIN; > + > + return 0; > +} > + > +static struct thermal_zone_device_ops tmu_tz_ops = { > + .get_temp = imx91_tmu_get_temp, > +}; > + > +static int imx91_init_from_nvmem_cells(struct imx91_tmu *tmu) > +{ > + struct device *dev = tmu->dev; > + int ret; > + u32 trim1, trim2; Please use the reverse christmas tree style. > + ret = nvmem_cell_read_u32(dev, "trim1", &trim1); > + if (ret) > + return ret; > + > + ret = nvmem_cell_read_u32(dev, "trim2", &trim2); > + if (ret) > + return ret; > + > + if (trim1 == 0 || trim2 == 0) > + return -EINVAL; > + > + writel_relaxed(trim1, tmu->base + TRIM1); > + writel_relaxed(trim2, tmu->base + TRIM2); > + > + return 0; > +} > + > +static int imx91_tmu_probe(struct platform_device *pdev) > +{ > + struct imx91_tmu *tmu; > + unsigned long rate; > + u32 div; > + int ret; > + int i = 0; Same here. > + tmu = devm_kzalloc(&pdev->dev, sizeof(struct imx91_tmu), GFP_KERNEL); > + if (!tmu) > + return -ENOMEM; > + > + tmu->dev = &pdev->dev; > + > + tmu->base = devm_platform_ioremap_resource(pdev, 0); > + if (IS_ERR(tmu->base)) > + return PTR_ERR(tmu->base); > + > + tmu->clk = devm_clk_get_prepared(&pdev->dev, NULL); > + if (IS_ERR(tmu->clk)) > + return dev_err_probe(&pdev->dev, PTR_ERR(tmu->clk), "failed to get tmu clock\n"); > + > + tmu->sensors.priv = tmu; As said, no need for the sensors container. > + tmu->sensors.tzd = devm_thermal_of_zone_register(&pdev->dev, i, &tmu->sensors, &tmu_tz_ops); > + if (IS_ERR(tmu->sensors.tzd)) > + return dev_err_probe(&pdev->dev, PTR_ERR(tmu->sensors.tzd), > + "failed to register thermal zone sensor\n"); > + > + platform_set_drvdata(pdev, tmu); > + > + /* disable the monitor during initialization */ > + imx91_tmu_enable(tmu, false); > + imx91_tmu_start(tmu, false); Make use of pm_runtime? > + ret = imx91_init_from_nvmem_cells(tmu); > + if (ret) { > + writel_relaxed(DEFAULT_TRIM1_CONFIG, tmu->base + TRIM1); > + writel_relaxed(DEFAULT_TRIM2_CONFIG, tmu->base + TRIM2); > + } > + > + /* The typical conv clk is 4MHz, the output freq is 'rate / (div + 1)' */ > + rate = clk_get_rate(tmu->clk); > + div = (rate / 4000000) - 1; Would be nice to validate the div value before passing to the HW and if the target rate of 4MHz can't be reached by the div you you should return -EINVAL. > + > + /* Set divider value and enable divider */ > + writel_relaxed(DIV_EN | FIELD_PREP(DIV_MASK, div), tmu->base + REF_DIV); > + > + /* Set max power up delay: 'Tpud(ms) = 0xFF * 1000 / 4000000' */ > + writel_relaxed(FIELD_PREP(PUDL_MASK, 100U), tmu->base + PUD_ST_CTRL); > + > + /* > + * Set resolution mode > + * 00b - Conversion time = 0.59325 ms > + * 01b - Conversion time = 1.10525 ms > + * 10b - Conversion time = 2.12925 ms > + * 11b - Conversion time = 4.17725 ms > + */ > + writel_relaxed(FIELD_PREP(CTRL1_RES_MASK, 0x3), tmu->base + CTRL1_CLR); > + writel_relaxed(FIELD_PREP(CTRL1_RES_MASK, 0x1), tmu->base + CTRL1_SET); > + > + /* > + * Set measure mode > + * 00b - Single oneshot measurement > + * 01b - Continuous measurement > + * 10b - Periodic oneshot measurement > + */ For the resolution it's fine to have the values directly coded without a define, but here we can definitly use a define and drop the comment. > + writel_relaxed(FIELD_PREP(CTRL1_MEAS_MODE_MASK, 0x3), tmu->base + CTRL1_CLR); > + writel_relaxed(FIELD_PREP(CTRL1_MEAS_MODE_MASK, 0x1), tmu->base + CTRL1_SET); Why do we set it to periodic mode instead of the single-shot? At the moment the device doesn't have IRQ support, and so there is no need to run the measurements in background. > + > + /* > + * Set Periodic Measurement Frequency to 25Hz: > + * tMEAS_FREQ = tCONV_CLK * PERIOD_CTRL[MEAS_FREQ]. -> > + * PERIOD_CTRL(MEAS_FREQ) = (1000 / 25) / (1000 / 4000000); > + * Where tMEAS_FREQ = Measurement period and tCONV_CLK = 1/fCONV_CLK. > + * This field should have value greater than count corresponds > + * to time greater than summation of conversion time, power up > + * delay, and six times of conversion clock time. > + * tMEAS_FREQ > (tCONV + tPUD + 6 * tCONV_CLK). > + * tCONV is conversion time determined by CTRL1[RESOLUTION]. > + */ > + writel_relaxed(FIELD_PREP(MEAS_FREQ_MASK, 0x27100), tmu->base + PERIOD_CTRL); With the single-shot measurements we could remove this part and.. > + > + /* enable the monitor */ > + imx91_tmu_enable(tmu, true); > + imx91_tmu_start(tmu, true); this part as well. Regards, Marco > + > + return 0; > +} > + > +static void imx91_tmu_remove(struct platform_device *pdev) > +{ > + struct imx91_tmu *tmu = platform_get_drvdata(pdev); > + > + /* disable tmu */ > + imx91_tmu_start(tmu, false); > + imx91_tmu_enable(tmu, false); > +} > + > +static int __maybe_unused imx91_tmu_suspend(struct device *dev) > +{ > + struct imx91_tmu *tmu = dev_get_drvdata(dev); > + > + /* disable tmu */ > + imx91_tmu_start(tmu, false); > + imx91_tmu_enable(tmu, false); > + > + clk_disable_unprepare(tmu->clk); > + > + return 0; > +} > + > +static int __maybe_unused imx91_tmu_resume(struct device *dev) > +{ > + struct imx91_tmu *tmu = dev_get_drvdata(dev); > + int ret; > + > + ret = clk_prepare_enable(tmu->clk); > + if (ret) > + return ret; > + > + imx91_tmu_enable(tmu, true); > + imx91_tmu_start(tmu, true); > + > + return 0; > +} > + > +static SIMPLE_DEV_PM_OPS(imx91_tmu_pm_ops, > + imx91_tmu_suspend, imx91_tmu_resume); > + > +static const struct of_device_id imx91_tmu_table[] = { > + { .compatible = "fsl,imx91-tmu", }, > + { }, > +}; > +MODULE_DEVICE_TABLE(of, imx91_tmu_table); > + > +static struct platform_driver imx91_tmu = { > + .driver = { > + .name = "i.MX91_thermal", > + .pm = pm_ptr(&imx91_tmu_pm_ops), > + .of_match_table = imx91_tmu_table, > + }, > + .probe = imx91_tmu_probe, > + .remove = imx91_tmu_remove, > +}; > +module_platform_driver(imx91_tmu); > + > +MODULE_AUTHOR("Peng Fan <peng.fan@nxp.com>"); > +MODULE_DESCRIPTION("i.MX91 Thermal Monitor Unit driver"); > +MODULE_LICENSE("GPL"); > > -- > 2.34.1 > > >
On Tue, Dec 10, 2024 at 11:36:46AM +0100, Marco Felsch wrote: > Hi, > > On 24-12-09, Frank Li wrote: > > From: Pengfei Li <pengfei.li_1@nxp.com> > > > > Introduce support for the i.MX91 thermal monitoring unit, which features a > > single sensor for the CPU. The register layout differs from other chips, > > necessitating the creation of a dedicated file for this. > > > > Signed-off-by: Pengfei Li <pengfei.li_1@nxp.com> > > Signed-off-by: Peng Fan <peng.fan@nxp.com> > > Signed-off-by: Frank Li <Frank.Li@nxp.com> > > --- > > drivers/thermal/Kconfig | 10 ++ > > drivers/thermal/Makefile | 1 + > > drivers/thermal/imx91_thermal.c | 281 ++++++++++++++++++++++++++++++++++++++++ > > 3 files changed, 292 insertions(+) > > > > diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig > > index d3f9686e26e71..da403ed86aeb1 100644 > > --- a/drivers/thermal/Kconfig > > +++ b/drivers/thermal/Kconfig > > @@ -296,6 +296,16 @@ config IMX8MM_THERMAL > > cpufreq is used as the cooling device to throttle CPUs when the passive > > trip is crossed. > > > > +config IMX91_THERMAL > > + tristate "Temperature sensor driver for NXP i.MX91 SoC" > > + depends on ARCH_MXC || COMPILE_TEST > > + depends on OF > > + help > > + Support for Temperature sensor found on NXP i.MX91 SoC. > > + It supports one critical trip point and one passive trip point. The > > + cpufreq is used as the cooling device to throttle CPUs when the passive > > + trip is crossed. > > + > > config K3_THERMAL > > tristate "Texas Instruments K3 thermal support" > > depends on ARCH_K3 || COMPILE_TEST > > diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile > > index 9abf43a74f2bb..08da241e6a598 100644 > > --- a/drivers/thermal/Makefile > > +++ b/drivers/thermal/Makefile > > @@ -50,6 +50,7 @@ obj-$(CONFIG_ARMADA_THERMAL) += armada_thermal.o > > obj-$(CONFIG_IMX_THERMAL) += imx_thermal.o > > obj-$(CONFIG_IMX_SC_THERMAL) += imx_sc_thermal.o > > obj-$(CONFIG_IMX8MM_THERMAL) += imx8mm_thermal.o > > +obj-$(CONFIG_IMX91_THERMAL) += imx91_thermal.o > > obj-$(CONFIG_MAX77620_THERMAL) += max77620_thermal.o > > obj-$(CONFIG_QORIQ_THERMAL) += qoriq_thermal.o > > obj-$(CONFIG_DA9062_THERMAL) += da9062-thermal.o > > diff --git a/drivers/thermal/imx91_thermal.c b/drivers/thermal/imx91_thermal.c > > new file mode 100644 > > index 0000000000000..19c4dafe9c7a9 > > --- /dev/null > > +++ b/drivers/thermal/imx91_thermal.c > > @@ -0,0 +1,281 @@ > > +// SPDX-License-Identifier: GPL-2.0 > > +/* > > + * Copyright 2024 NXP. > > + */ > > + > > +#include <linux/bitfield.h> > > +#include <linux/clk.h> > > +#include <linux/err.h> > > +#include <linux/iopoll.h> > > +#include <linux/nvmem-consumer.h> > > +#include <linux/module.h> > > +#include <linux/of.h> > > +#include <linux/of_device.h> > > +#include <linux/platform_device.h> > > +#include <linux/thermal.h> > > + > > +#define CTRL0 0x0 > > + > > +#define STAT0 0x10 > > +#define STAT0_DRDY0_IF_MASK BIT(16) > > + > > +#define DATA0 0x20 > > +#define DATA_INT_MASK GENMASK(14, 7) > > +#define DATA_FRAC_MASK GENMASK(6, 0) > > + > > +#define THR_CTRL01 0x30 > > +#define THR_CTRL23 0x40 > > + > > +#define CTRL1 0x200 > > +#define CTRL1_SET 0x204 > > +#define CTRL1_CLR 0x208 > > +#define CTRL1_EN BIT(31) > > +#define CTRL1_START BIT(30) > > +#define CTRL1_STOP BIT(29) > > +#define CTRL1_RES_MASK GENMASK(19, 18) > > +#define CTRL1_MEAS_MODE_MASK GENMASK(25, 24) > > + > > +#define PERIOD_CTRL 0x270 > > +#define MEAS_FREQ_MASK GENMASK(23, 0) > > + > > +#define REF_DIV 0x280 > > +#define DIV_EN BIT(31) > > +#define DIV_MASK GENMASK(23, 16) > > + > > +#define PUD_ST_CTRL 0x2B0 > > +#define PUDL_MASK GENMASK(23, 16) > > + > > +#define TRIM1 0x2E0 > > +#define TRIM2 0x2F0 > > + > > +#define TMU_TEMP_LOW_LIMIT -40000 > > +#define TMU_TEMP_HIGH_LIMIT 125000 > > + > > +#define DEFAULT_TRIM1_CONFIG 0xB561BC2DU > > +#define DEFAULT_TRIM2_CONFIG 0x65D4U > > please align the defines and use lower-case for the hex values. > > > +struct tmu_sensor { > > + struct imx91_tmu *priv; > > + struct thermal_zone_device *tzd; > > +}; > > This can be part of imx91_tmu right? > > > +struct imx91_tmu { > > + void __iomem *base; > > + struct clk *clk; > > + struct device *dev; > > + struct tmu_sensor sensors; > > +}; > > + > > +static void imx91_tmu_start(struct imx91_tmu *tmu, bool start) > > +{ > > + if (start) > > + writel_relaxed(CTRL1_START, tmu->base + CTRL1_SET); > > + else > > + writel_relaxed(CTRL1_STOP, tmu->base + CTRL1_SET); > > Nit: > unsigned int val = start ? CTRL1_START : CTRL1_STOP; > > writel_relaxed(val, tmu->base + CTRL1_SET); > > Aside the nit, why do you use *_relaxed() accessors in you whole code? > Is the order not strictly required? > > > +} > > + > > +static void imx91_tmu_enable(struct imx91_tmu *tmu, bool enable) > > +{ > > + if (enable) > > + writel_relaxed(CTRL1_EN, tmu->base + CTRL1_SET); > > + else > > + writel_relaxed(CTRL1_EN, tmu->base + CTRL1_CLR); > > Same here: > > unsigned int reg = enable ? CTRL1_SET : CTRL1_CLR; > > writel_relaxed(CTRL1_EN, tmu->base + reg); > > +} > > + > > +static int imx91_tmu_get_temp(struct thermal_zone_device *tz, int *temp) > > +{ > > + struct tmu_sensor *sensor = thermal_zone_device_priv(tz); > > + struct imx91_tmu *tmu = sensor->priv; > > With tmu_sensor merged into imx91_tmu you don't need this reverse > pointer logic. > > > + int val; > > + int ret; > > + > > + ret = readl_relaxed_poll_timeout(tmu->base + STAT0, val, > > + val & STAT0_DRDY0_IF_MASK, 1000, > > + 40000); > > + if (ret) > > + return -EAGAIN; > > + > > + val = readl_relaxed(tmu->base + DATA0) & 0xffffU; > ^ > Please use a MASK define for it, also no > need to use the U suffix. > > Also according the TRM 58.3.4 this doesn't seem right. According the TRM > this is a s16 (two's-complement) value. You won't get negative values if > store it within a int. > > > + *temp = val * 1000L / 64L; > ^ ^ > You don't need to specify the type here explicit since all params would > be converted to int and no overflow happens. > > > + if (*temp < TMU_TEMP_LOW_LIMIT || *temp > TMU_TEMP_HIGH_LIMIT) > > + return -EAGAIN; > > + > > + return 0; > > +} > > + > > +static struct thermal_zone_device_ops tmu_tz_ops = { > > + .get_temp = imx91_tmu_get_temp, > > +}; > > + > > +static int imx91_init_from_nvmem_cells(struct imx91_tmu *tmu) > > +{ > > + struct device *dev = tmu->dev; > > + int ret; > > + u32 trim1, trim2; > > Please use the reverse christmas tree style. > > > + ret = nvmem_cell_read_u32(dev, "trim1", &trim1); > > + if (ret) > > + return ret; > > + > > + ret = nvmem_cell_read_u32(dev, "trim2", &trim2); > > + if (ret) > > + return ret; > > + > > + if (trim1 == 0 || trim2 == 0) > > + return -EINVAL; > > + > > + writel_relaxed(trim1, tmu->base + TRIM1); > > + writel_relaxed(trim2, tmu->base + TRIM2); > > + > > + return 0; > > +} > > + > > +static int imx91_tmu_probe(struct platform_device *pdev) > > +{ > > + struct imx91_tmu *tmu; > > + unsigned long rate; > > + u32 div; > > + int ret; > > + int i = 0; > > Same here. > > > + tmu = devm_kzalloc(&pdev->dev, sizeof(struct imx91_tmu), GFP_KERNEL); > > + if (!tmu) > > + return -ENOMEM; > > + > > + tmu->dev = &pdev->dev; > > + > > + tmu->base = devm_platform_ioremap_resource(pdev, 0); > > + if (IS_ERR(tmu->base)) > > + return PTR_ERR(tmu->base); > > + > > + tmu->clk = devm_clk_get_prepared(&pdev->dev, NULL); > > + if (IS_ERR(tmu->clk)) > > + return dev_err_probe(&pdev->dev, PTR_ERR(tmu->clk), "failed to get tmu clock\n"); > > + > > + tmu->sensors.priv = tmu; > > As said, no need for the sensors container. > > > + tmu->sensors.tzd = devm_thermal_of_zone_register(&pdev->dev, i, &tmu->sensors, &tmu_tz_ops); > > + if (IS_ERR(tmu->sensors.tzd)) > > + return dev_err_probe(&pdev->dev, PTR_ERR(tmu->sensors.tzd), > > + "failed to register thermal zone sensor\n"); > > + > > + platform_set_drvdata(pdev, tmu); > > + > > + /* disable the monitor during initialization */ > > + imx91_tmu_enable(tmu, false); > > + imx91_tmu_start(tmu, false); > > Make use of pm_runtime? thermal is always on after probe. continue measure tempature. So pm_runtime is not suitable for this case. > > > + ret = imx91_init_from_nvmem_cells(tmu); > > + if (ret) { > > + writel_relaxed(DEFAULT_TRIM1_CONFIG, tmu->base + TRIM1); > > + writel_relaxed(DEFAULT_TRIM2_CONFIG, tmu->base + TRIM2); > > + } > > + > > + /* The typical conv clk is 4MHz, the output freq is 'rate / (div + 1)' */ > > + rate = clk_get_rate(tmu->clk); > > + div = (rate / 4000000) - 1; > > Would be nice to validate the div value before passing to the HW and if > the target rate of 4MHz can't be reached by the div you you should > return -EINVAL. > > > + > > + /* Set divider value and enable divider */ > > + writel_relaxed(DIV_EN | FIELD_PREP(DIV_MASK, div), tmu->base + REF_DIV); > > + > > + /* Set max power up delay: 'Tpud(ms) = 0xFF * 1000 / 4000000' */ > > + writel_relaxed(FIELD_PREP(PUDL_MASK, 100U), tmu->base + PUD_ST_CTRL); > > + > > + /* > > + * Set resolution mode > > + * 00b - Conversion time = 0.59325 ms > > + * 01b - Conversion time = 1.10525 ms > > + * 10b - Conversion time = 2.12925 ms > > + * 11b - Conversion time = 4.17725 ms > > + */ > > + writel_relaxed(FIELD_PREP(CTRL1_RES_MASK, 0x3), tmu->base + CTRL1_CLR); > > + writel_relaxed(FIELD_PREP(CTRL1_RES_MASK, 0x1), tmu->base + CTRL1_SET); > > + > > + /* > > + * Set measure mode > > + * 00b - Single oneshot measurement > > + * 01b - Continuous measurement > > + * 10b - Periodic oneshot measurement > > + */ > > For the resolution it's fine to have the values directly coded without a > define, but here we can definitly use a define and drop the comment. > > > + writel_relaxed(FIELD_PREP(CTRL1_MEAS_MODE_MASK, 0x3), tmu->base + CTRL1_CLR); > > + writel_relaxed(FIELD_PREP(CTRL1_MEAS_MODE_MASK, 0x1), tmu->base + CTRL1_SET); > > Why do we set it to periodic mode instead of the single-shot? At the > moment the device doesn't have IRQ support, and so there is no need to > run the measurements in background. It is "continous measurement". first clean MODE_MASK, then then 01. _CLR means clean bits according to mask _SET means set bits according to mask. Frank > > > + > > + /* > > + * Set Periodic Measurement Frequency to 25Hz: > > + * tMEAS_FREQ = tCONV_CLK * PERIOD_CTRL[MEAS_FREQ]. -> > > + * PERIOD_CTRL(MEAS_FREQ) = (1000 / 25) / (1000 / 4000000); > > + * Where tMEAS_FREQ = Measurement period and tCONV_CLK = 1/fCONV_CLK. > > + * This field should have value greater than count corresponds > > + * to time greater than summation of conversion time, power up > > + * delay, and six times of conversion clock time. > > + * tMEAS_FREQ > (tCONV + tPUD + 6 * tCONV_CLK). > > + * tCONV is conversion time determined by CTRL1[RESOLUTION]. > > + */ > > + writel_relaxed(FIELD_PREP(MEAS_FREQ_MASK, 0x27100), tmu->base + PERIOD_CTRL); > > With the single-shot measurements we could remove this part and.. > > > + > > + /* enable the monitor */ > > + imx91_tmu_enable(tmu, true); > > + imx91_tmu_start(tmu, true); > > this part as well. > > Regards, > Marco > > > + > > + return 0; > > +} > > + > > +static void imx91_tmu_remove(struct platform_device *pdev) > > +{ > > + struct imx91_tmu *tmu = platform_get_drvdata(pdev); > > + > > + /* disable tmu */ > > + imx91_tmu_start(tmu, false); > > + imx91_tmu_enable(tmu, false); > > +} > > + > > +static int __maybe_unused imx91_tmu_suspend(struct device *dev) > > +{ > > + struct imx91_tmu *tmu = dev_get_drvdata(dev); > > + > > + /* disable tmu */ > > + imx91_tmu_start(tmu, false); > > + imx91_tmu_enable(tmu, false); > > + > > + clk_disable_unprepare(tmu->clk); > > + > > + return 0; > > +} > > + > > +static int __maybe_unused imx91_tmu_resume(struct device *dev) > > +{ > > + struct imx91_tmu *tmu = dev_get_drvdata(dev); > > + int ret; > > + > > + ret = clk_prepare_enable(tmu->clk); > > + if (ret) > > + return ret; > > + > > + imx91_tmu_enable(tmu, true); > > + imx91_tmu_start(tmu, true); > > + > > + return 0; > > +} > > + > > +static SIMPLE_DEV_PM_OPS(imx91_tmu_pm_ops, > > + imx91_tmu_suspend, imx91_tmu_resume); > > + > > +static const struct of_device_id imx91_tmu_table[] = { > > + { .compatible = "fsl,imx91-tmu", }, > > + { }, > > +}; > > +MODULE_DEVICE_TABLE(of, imx91_tmu_table); > > + > > +static struct platform_driver imx91_tmu = { > > + .driver = { > > + .name = "i.MX91_thermal", > > + .pm = pm_ptr(&imx91_tmu_pm_ops), > > + .of_match_table = imx91_tmu_table, > > + }, > > + .probe = imx91_tmu_probe, > > + .remove = imx91_tmu_remove, > > +}; > > +module_platform_driver(imx91_tmu); > > + > > +MODULE_AUTHOR("Peng Fan <peng.fan@nxp.com>"); > > +MODULE_DESCRIPTION("i.MX91 Thermal Monitor Unit driver"); > > +MODULE_LICENSE("GPL"); > > > > -- > > 2.34.1 > > > > > >
On 24-12-10, Frank Li wrote: > On Tue, Dec 10, 2024 at 11:36:46AM +0100, Marco Felsch wrote: > > Hi, > > > > On 24-12-09, Frank Li wrote: ... > > > + /* disable the monitor during initialization */ > > > + imx91_tmu_enable(tmu, false); > > > + imx91_tmu_start(tmu, false); > > > > Make use of pm_runtime? > > thermal is always on after probe. continue measure tempature. So pm_runtime > is not suitable for this case. There are at least 3 drivers which use pm-runtime including the i.MX6/7 imx_thermal.c driver. > > > + ret = imx91_init_from_nvmem_cells(tmu); > > > + if (ret) { > > > + writel_relaxed(DEFAULT_TRIM1_CONFIG, tmu->base + TRIM1); > > > + writel_relaxed(DEFAULT_TRIM2_CONFIG, tmu->base + TRIM2); > > > + } > > > + > > > + /* The typical conv clk is 4MHz, the output freq is 'rate / (div + 1)' */ > > > + rate = clk_get_rate(tmu->clk); > > > + div = (rate / 4000000) - 1; > > > > Would be nice to validate the div value before passing to the HW and if > > the target rate of 4MHz can't be reached by the div you you should > > return -EINVAL. > > > > > + > > > + /* Set divider value and enable divider */ > > > + writel_relaxed(DIV_EN | FIELD_PREP(DIV_MASK, div), tmu->base + REF_DIV); > > > + > > > + /* Set max power up delay: 'Tpud(ms) = 0xFF * 1000 / 4000000' */ > > > + writel_relaxed(FIELD_PREP(PUDL_MASK, 100U), tmu->base + PUD_ST_CTRL); > > > + > > > + /* > > > + * Set resolution mode > > > + * 00b - Conversion time = 0.59325 ms > > > + * 01b - Conversion time = 1.10525 ms > > > + * 10b - Conversion time = 2.12925 ms > > > + * 11b - Conversion time = 4.17725 ms > > > + */ > > > + writel_relaxed(FIELD_PREP(CTRL1_RES_MASK, 0x3), tmu->base + CTRL1_CLR); > > > + writel_relaxed(FIELD_PREP(CTRL1_RES_MASK, 0x1), tmu->base + CTRL1_SET); > > > + > > > + /* > > > + * Set measure mode > > > + * 00b - Single oneshot measurement > > > + * 01b - Continuous measurement > > > + * 10b - Periodic oneshot measurement > > > + */ > > > > For the resolution it's fine to have the values directly coded without a > > define, but here we can definitly use a define and drop the comment. > > > > > + writel_relaxed(FIELD_PREP(CTRL1_MEAS_MODE_MASK, 0x3), tmu->base + CTRL1_CLR); > > > + writel_relaxed(FIELD_PREP(CTRL1_MEAS_MODE_MASK, 0x1), tmu->base + CTRL1_SET); > > > > Why do we set it to periodic mode instead of the single-shot? At the > > moment the device doesn't have IRQ support, and so there is no need to > > run the measurements in background. > > It is "continous measurement". first clean MODE_MASK, then then 01. Still, why? You return the temp value upon a request (get_temp). There is no async notification from this driver to others. So it can be left to single-shot and do the measurement on request (get_temp). > _CLR means clean bits according to mask > _SET means set bits according to mask. I know. Regards, Marco > > Frank > > > > > > + > > > + /* > > > + * Set Periodic Measurement Frequency to 25Hz: > > > + * tMEAS_FREQ = tCONV_CLK * PERIOD_CTRL[MEAS_FREQ]. -> > > > + * PERIOD_CTRL(MEAS_FREQ) = (1000 / 25) / (1000 / 4000000); > > > + * Where tMEAS_FREQ = Measurement period and tCONV_CLK = 1/fCONV_CLK. > > > + * This field should have value greater than count corresponds > > > + * to time greater than summation of conversion time, power up > > > + * delay, and six times of conversion clock time. > > > + * tMEAS_FREQ > (tCONV + tPUD + 6 * tCONV_CLK). > > > + * tCONV is conversion time determined by CTRL1[RESOLUTION]. > > > + */ > > > + writel_relaxed(FIELD_PREP(MEAS_FREQ_MASK, 0x27100), tmu->base + PERIOD_CTRL); > > > > With the single-shot measurements we could remove this part and.. > > > > > + > > > + /* enable the monitor */ > > > + imx91_tmu_enable(tmu, true); > > > + imx91_tmu_start(tmu, true); > > > > this part as well. > > > > Regards, > > Marco > > > > > + > > > + return 0; > > > +} > > > + > > > +static void imx91_tmu_remove(struct platform_device *pdev) > > > +{ > > > + struct imx91_tmu *tmu = platform_get_drvdata(pdev); > > > + > > > + /* disable tmu */ > > > + imx91_tmu_start(tmu, false); > > > + imx91_tmu_enable(tmu, false); > > > +} > > > + > > > +static int __maybe_unused imx91_tmu_suspend(struct device *dev) > > > +{ > > > + struct imx91_tmu *tmu = dev_get_drvdata(dev); > > > + > > > + /* disable tmu */ > > > + imx91_tmu_start(tmu, false); > > > + imx91_tmu_enable(tmu, false); > > > + > > > + clk_disable_unprepare(tmu->clk); > > > + > > > + return 0; > > > +} > > > + > > > +static int __maybe_unused imx91_tmu_resume(struct device *dev) > > > +{ > > > + struct imx91_tmu *tmu = dev_get_drvdata(dev); > > > + int ret; > > > + > > > + ret = clk_prepare_enable(tmu->clk); > > > + if (ret) > > > + return ret; > > > + > > > + imx91_tmu_enable(tmu, true); > > > + imx91_tmu_start(tmu, true); > > > + > > > + return 0; > > > +} > > > + > > > +static SIMPLE_DEV_PM_OPS(imx91_tmu_pm_ops, > > > + imx91_tmu_suspend, imx91_tmu_resume); > > > + > > > +static const struct of_device_id imx91_tmu_table[] = { > > > + { .compatible = "fsl,imx91-tmu", }, > > > + { }, > > > +}; > > > +MODULE_DEVICE_TABLE(of, imx91_tmu_table); > > > + > > > +static struct platform_driver imx91_tmu = { > > > + .driver = { > > > + .name = "i.MX91_thermal", > > > + .pm = pm_ptr(&imx91_tmu_pm_ops), > > > + .of_match_table = imx91_tmu_table, > > > + }, > > > + .probe = imx91_tmu_probe, > > > + .remove = imx91_tmu_remove, > > > +}; > > > +module_platform_driver(imx91_tmu); > > > + > > > +MODULE_AUTHOR("Peng Fan <peng.fan@nxp.com>"); > > > +MODULE_DESCRIPTION("i.MX91 Thermal Monitor Unit driver"); > > > +MODULE_LICENSE("GPL"); > > > > > > -- > > > 2.34.1 > > > > > > > > > >
diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig index d3f9686e26e71..da403ed86aeb1 100644 --- a/drivers/thermal/Kconfig +++ b/drivers/thermal/Kconfig @@ -296,6 +296,16 @@ config IMX8MM_THERMAL cpufreq is used as the cooling device to throttle CPUs when the passive trip is crossed. +config IMX91_THERMAL + tristate "Temperature sensor driver for NXP i.MX91 SoC" + depends on ARCH_MXC || COMPILE_TEST + depends on OF + help + Support for Temperature sensor found on NXP i.MX91 SoC. + It supports one critical trip point and one passive trip point. The + cpufreq is used as the cooling device to throttle CPUs when the passive + trip is crossed. + config K3_THERMAL tristate "Texas Instruments K3 thermal support" depends on ARCH_K3 || COMPILE_TEST diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile index 9abf43a74f2bb..08da241e6a598 100644 --- a/drivers/thermal/Makefile +++ b/drivers/thermal/Makefile @@ -50,6 +50,7 @@ obj-$(CONFIG_ARMADA_THERMAL) += armada_thermal.o obj-$(CONFIG_IMX_THERMAL) += imx_thermal.o obj-$(CONFIG_IMX_SC_THERMAL) += imx_sc_thermal.o obj-$(CONFIG_IMX8MM_THERMAL) += imx8mm_thermal.o +obj-$(CONFIG_IMX91_THERMAL) += imx91_thermal.o obj-$(CONFIG_MAX77620_THERMAL) += max77620_thermal.o obj-$(CONFIG_QORIQ_THERMAL) += qoriq_thermal.o obj-$(CONFIG_DA9062_THERMAL) += da9062-thermal.o diff --git a/drivers/thermal/imx91_thermal.c b/drivers/thermal/imx91_thermal.c new file mode 100644 index 0000000000000..19c4dafe9c7a9 --- /dev/null +++ b/drivers/thermal/imx91_thermal.c @@ -0,0 +1,281 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright 2024 NXP. + */ + +#include <linux/bitfield.h> +#include <linux/clk.h> +#include <linux/err.h> +#include <linux/iopoll.h> +#include <linux/nvmem-consumer.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/thermal.h> + +#define CTRL0 0x0 + +#define STAT0 0x10 +#define STAT0_DRDY0_IF_MASK BIT(16) + +#define DATA0 0x20 +#define DATA_INT_MASK GENMASK(14, 7) +#define DATA_FRAC_MASK GENMASK(6, 0) + +#define THR_CTRL01 0x30 +#define THR_CTRL23 0x40 + +#define CTRL1 0x200 +#define CTRL1_SET 0x204 +#define CTRL1_CLR 0x208 +#define CTRL1_EN BIT(31) +#define CTRL1_START BIT(30) +#define CTRL1_STOP BIT(29) +#define CTRL1_RES_MASK GENMASK(19, 18) +#define CTRL1_MEAS_MODE_MASK GENMASK(25, 24) + +#define PERIOD_CTRL 0x270 +#define MEAS_FREQ_MASK GENMASK(23, 0) + +#define REF_DIV 0x280 +#define DIV_EN BIT(31) +#define DIV_MASK GENMASK(23, 16) + +#define PUD_ST_CTRL 0x2B0 +#define PUDL_MASK GENMASK(23, 16) + +#define TRIM1 0x2E0 +#define TRIM2 0x2F0 + +#define TMU_TEMP_LOW_LIMIT -40000 +#define TMU_TEMP_HIGH_LIMIT 125000 + +#define DEFAULT_TRIM1_CONFIG 0xB561BC2DU +#define DEFAULT_TRIM2_CONFIG 0x65D4U + +struct tmu_sensor { + struct imx91_tmu *priv; + struct thermal_zone_device *tzd; +}; + +struct imx91_tmu { + void __iomem *base; + struct clk *clk; + struct device *dev; + struct tmu_sensor sensors; +}; + +static void imx91_tmu_start(struct imx91_tmu *tmu, bool start) +{ + if (start) + writel_relaxed(CTRL1_START, tmu->base + CTRL1_SET); + else + writel_relaxed(CTRL1_STOP, tmu->base + CTRL1_SET); +} + +static void imx91_tmu_enable(struct imx91_tmu *tmu, bool enable) +{ + if (enable) + writel_relaxed(CTRL1_EN, tmu->base + CTRL1_SET); + else + writel_relaxed(CTRL1_EN, tmu->base + CTRL1_CLR); +} + +static int imx91_tmu_get_temp(struct thermal_zone_device *tz, int *temp) +{ + struct tmu_sensor *sensor = thermal_zone_device_priv(tz); + struct imx91_tmu *tmu = sensor->priv; + int val; + int ret; + + ret = readl_relaxed_poll_timeout(tmu->base + STAT0, val, + val & STAT0_DRDY0_IF_MASK, 1000, + 40000); + if (ret) + return -EAGAIN; + + val = readl_relaxed(tmu->base + DATA0) & 0xffffU; + *temp = val * 1000L / 64L; + if (*temp < TMU_TEMP_LOW_LIMIT || *temp > TMU_TEMP_HIGH_LIMIT) + return -EAGAIN; + + return 0; +} + +static struct thermal_zone_device_ops tmu_tz_ops = { + .get_temp = imx91_tmu_get_temp, +}; + +static int imx91_init_from_nvmem_cells(struct imx91_tmu *tmu) +{ + struct device *dev = tmu->dev; + int ret; + u32 trim1, trim2; + + ret = nvmem_cell_read_u32(dev, "trim1", &trim1); + if (ret) + return ret; + + ret = nvmem_cell_read_u32(dev, "trim2", &trim2); + if (ret) + return ret; + + if (trim1 == 0 || trim2 == 0) + return -EINVAL; + + writel_relaxed(trim1, tmu->base + TRIM1); + writel_relaxed(trim2, tmu->base + TRIM2); + + return 0; +} + +static int imx91_tmu_probe(struct platform_device *pdev) +{ + struct imx91_tmu *tmu; + unsigned long rate; + u32 div; + int ret; + int i = 0; + + tmu = devm_kzalloc(&pdev->dev, sizeof(struct imx91_tmu), GFP_KERNEL); + if (!tmu) + return -ENOMEM; + + tmu->dev = &pdev->dev; + + tmu->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(tmu->base)) + return PTR_ERR(tmu->base); + + tmu->clk = devm_clk_get_prepared(&pdev->dev, NULL); + if (IS_ERR(tmu->clk)) + return dev_err_probe(&pdev->dev, PTR_ERR(tmu->clk), "failed to get tmu clock\n"); + + tmu->sensors.priv = tmu; + tmu->sensors.tzd = devm_thermal_of_zone_register(&pdev->dev, i, &tmu->sensors, &tmu_tz_ops); + if (IS_ERR(tmu->sensors.tzd)) + return dev_err_probe(&pdev->dev, PTR_ERR(tmu->sensors.tzd), + "failed to register thermal zone sensor\n"); + + platform_set_drvdata(pdev, tmu); + + /* disable the monitor during initialization */ + imx91_tmu_enable(tmu, false); + imx91_tmu_start(tmu, false); + + ret = imx91_init_from_nvmem_cells(tmu); + if (ret) { + writel_relaxed(DEFAULT_TRIM1_CONFIG, tmu->base + TRIM1); + writel_relaxed(DEFAULT_TRIM2_CONFIG, tmu->base + TRIM2); + } + + /* The typical conv clk is 4MHz, the output freq is 'rate / (div + 1)' */ + rate = clk_get_rate(tmu->clk); + div = (rate / 4000000) - 1; + + /* Set divider value and enable divider */ + writel_relaxed(DIV_EN | FIELD_PREP(DIV_MASK, div), tmu->base + REF_DIV); + + /* Set max power up delay: 'Tpud(ms) = 0xFF * 1000 / 4000000' */ + writel_relaxed(FIELD_PREP(PUDL_MASK, 100U), tmu->base + PUD_ST_CTRL); + + /* + * Set resolution mode + * 00b - Conversion time = 0.59325 ms + * 01b - Conversion time = 1.10525 ms + * 10b - Conversion time = 2.12925 ms + * 11b - Conversion time = 4.17725 ms + */ + writel_relaxed(FIELD_PREP(CTRL1_RES_MASK, 0x3), tmu->base + CTRL1_CLR); + writel_relaxed(FIELD_PREP(CTRL1_RES_MASK, 0x1), tmu->base + CTRL1_SET); + + /* + * Set measure mode + * 00b - Single oneshot measurement + * 01b - Continuous measurement + * 10b - Periodic oneshot measurement + */ + writel_relaxed(FIELD_PREP(CTRL1_MEAS_MODE_MASK, 0x3), tmu->base + CTRL1_CLR); + writel_relaxed(FIELD_PREP(CTRL1_MEAS_MODE_MASK, 0x1), tmu->base + CTRL1_SET); + + /* + * Set Periodic Measurement Frequency to 25Hz: + * tMEAS_FREQ = tCONV_CLK * PERIOD_CTRL[MEAS_FREQ]. -> + * PERIOD_CTRL(MEAS_FREQ) = (1000 / 25) / (1000 / 4000000); + * Where tMEAS_FREQ = Measurement period and tCONV_CLK = 1/fCONV_CLK. + * This field should have value greater than count corresponds + * to time greater than summation of conversion time, power up + * delay, and six times of conversion clock time. + * tMEAS_FREQ > (tCONV + tPUD + 6 * tCONV_CLK). + * tCONV is conversion time determined by CTRL1[RESOLUTION]. + */ + writel_relaxed(FIELD_PREP(MEAS_FREQ_MASK, 0x27100), tmu->base + PERIOD_CTRL); + + /* enable the monitor */ + imx91_tmu_enable(tmu, true); + imx91_tmu_start(tmu, true); + + return 0; +} + +static void imx91_tmu_remove(struct platform_device *pdev) +{ + struct imx91_tmu *tmu = platform_get_drvdata(pdev); + + /* disable tmu */ + imx91_tmu_start(tmu, false); + imx91_tmu_enable(tmu, false); +} + +static int __maybe_unused imx91_tmu_suspend(struct device *dev) +{ + struct imx91_tmu *tmu = dev_get_drvdata(dev); + + /* disable tmu */ + imx91_tmu_start(tmu, false); + imx91_tmu_enable(tmu, false); + + clk_disable_unprepare(tmu->clk); + + return 0; +} + +static int __maybe_unused imx91_tmu_resume(struct device *dev) +{ + struct imx91_tmu *tmu = dev_get_drvdata(dev); + int ret; + + ret = clk_prepare_enable(tmu->clk); + if (ret) + return ret; + + imx91_tmu_enable(tmu, true); + imx91_tmu_start(tmu, true); + + return 0; +} + +static SIMPLE_DEV_PM_OPS(imx91_tmu_pm_ops, + imx91_tmu_suspend, imx91_tmu_resume); + +static const struct of_device_id imx91_tmu_table[] = { + { .compatible = "fsl,imx91-tmu", }, + { }, +}; +MODULE_DEVICE_TABLE(of, imx91_tmu_table); + +static struct platform_driver imx91_tmu = { + .driver = { + .name = "i.MX91_thermal", + .pm = pm_ptr(&imx91_tmu_pm_ops), + .of_match_table = imx91_tmu_table, + }, + .probe = imx91_tmu_probe, + .remove = imx91_tmu_remove, +}; +module_platform_driver(imx91_tmu); + +MODULE_AUTHOR("Peng Fan <peng.fan@nxp.com>"); +MODULE_DESCRIPTION("i.MX91 Thermal Monitor Unit driver"); +MODULE_LICENSE("GPL");