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authorDapeng Mi <dapeng1.mi@linux.intel.com>2026-09-17 09:52:33 +0800
committerIngo Molnar <mingo@kernel.org>2026-09-22 11:37:46 +0200
commit0102c8c7fdfc4bd700971daff2b94470f4eafae4 (patch)
tree531306c2299f9a269f0a986e29f17ba972180104 /drivers/hwmon/ads7871.c
downloadlinux-stable-0102c8c7fdfc4bd700971daff2b94470f4eafae4.tar.gz
linux-stable-0102c8c7fdfc4bd700971daff2b94470f4eafae4.zip
perf/x86/intel: Rename DMR offcore_rsp attribute to offmodule_rspgrafted
DMR introduces Offmodule Response events in place of the legacy Offcore Response events, but it still exposes the inherited offcore_rsp PMU attribute for programming the corresponding MSR data. Rename the DMR PMU attribute to offmodule_rsp so the sysfs interface matches the underlying event name and avoids user & tooling confusion. Signed-off-by: Dapeng Mi <dapeng1.mi@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://patch.msgid.link/20260917015234.981153-12-dapeng1.mi@linux.intel.com
Diffstat (limited to 'drivers/hwmon/ads7871.c')
-rw-r--r--drivers/hwmon/ads7871.c231
1 files changed, 231 insertions, 0 deletions
diff --git a/drivers/hwmon/ads7871.c b/drivers/hwmon/ads7871.c
new file mode 100644
index 000000000..d1cbff0e8
--- /dev/null
+++ b/drivers/hwmon/ads7871.c
@@ -0,0 +1,231 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * ads7871 - driver for TI ADS7871 A/D converter
+ *
+ * Copyright (c) 2010 Paul Thomas <pthomas8589@gmail.com>
+ *
+ * You need to have something like this in struct spi_board_info
+ * {
+ * .modalias = "ads7871",
+ * .max_speed_hz = 2*1000*1000,
+ * .chip_select = 0,
+ * .bus_num = 1,
+ * },
+ */
+
+/*From figure 18 in the datasheet*/
+/*Register addresses*/
+#define REG_LS_BYTE 0 /*A/D Output Data, LS Byte*/
+#define REG_MS_BYTE 1 /*A/D Output Data, MS Byte*/
+#define REG_PGA_VALID 2 /*PGA Valid Register*/
+#define REG_AD_CONTROL 3 /*A/D Control Register*/
+#define REG_GAIN_MUX 4 /*Gain/Mux Register*/
+#define REG_IO_STATE 5 /*Digital I/O State Register*/
+#define REG_IO_CONTROL 6 /*Digital I/O Control Register*/
+#define REG_OSC_CONTROL 7 /*Rev/Oscillator Control Register*/
+#define REG_SER_CONTROL 24 /*Serial Interface Control Register*/
+#define REG_ID 31 /*ID Register*/
+
+/*
+ * From figure 17 in the datasheet
+ * These bits get ORed with the address to form
+ * the instruction byte
+ */
+/*Instruction Bit masks*/
+#define INST_MODE_BM (1 << 7)
+#define INST_READ_BM (1 << 6)
+#define INST_16BIT_BM (1 << 5)
+
+/*From figure 18 in the datasheet*/
+/*bit masks for Rev/Oscillator Control Register*/
+#define MUX_CNV_BV 7
+#define MUX_CNV_BM (1 << MUX_CNV_BV)
+#define MUX_M3_BM (1 << 3) /*M3 selects single ended*/
+#define MUX_G_BV 4 /*allows for reg = (gain << MUX_G_BV) | ...*/
+
+/*From figure 18 in the datasheet*/
+/*bit masks for Rev/Oscillator Control Register*/
+#define OSC_OSCR_BM (1 << 5)
+#define OSC_OSCE_BM (1 << 4)
+#define OSC_REFE_BM (1 << 3)
+#define OSC_BUFE_BM (1 << 2)
+#define OSC_R2V_BM (1 << 1)
+#define OSC_RBG_BM (1 << 0)
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/spi/spi.h>
+#include <linux/hwmon.h>
+#include <linux/err.h>
+#include <linux/delay.h>
+
+#define DEVICE_NAME "ads7871"
+
+struct ads7871_data {
+ struct spi_device *spi;
+ u8 tx_buf[2] ____cacheline_aligned;
+};
+
+static umode_t ads7871_is_visible(const void *data,
+ enum hwmon_sensor_types type,
+ u32 attr, int channel)
+{
+ if (type == hwmon_in && attr == hwmon_in_input)
+ return 0444;
+
+ return 0;
+}
+
+static int ads7871_read_reg8(struct spi_device *spi, int reg)
+{
+ int ret;
+ reg = reg | INST_READ_BM;
+ ret = spi_w8r8(spi, reg);
+ return ret;
+}
+
+static int ads7871_read_reg16(struct spi_device *spi, int reg)
+{
+ int ret;
+
+ reg = reg | INST_READ_BM | INST_16BIT_BM;
+ ret = spi_w8r16(spi, reg);
+ if (ret < 0)
+ return ret;
+
+ return le16_to_cpu((__force __le16)ret);
+}
+
+static int ads7871_write_reg8(struct ads7871_data *pdata, int reg, u8 val)
+{
+ pdata->tx_buf[0] = reg;
+ pdata->tx_buf[1] = val;
+
+ return spi_write(pdata->spi, pdata->tx_buf, 2);
+}
+
+static int ads7871_read(struct device *dev, enum hwmon_sensor_types type,
+ u32 attr, int channel, long *val)
+{
+ struct ads7871_data *pdata = dev_get_drvdata(dev);
+ struct spi_device *spi = pdata->spi;
+ int ret, raw_val, i = 0;
+ u8 mux_cnv;
+
+ if (type != hwmon_in || attr != hwmon_in_input)
+ return -EOPNOTSUPP;
+ /*
+ * TODO: add support for conversions
+ * other than single ended with a gain of 1
+ */
+ /*MUX_M3_BM forces single ended*/
+ /*This is also where the gain of the PGA would be set*/
+ ret = ads7871_write_reg8(pdata, REG_GAIN_MUX,
+ (MUX_CNV_BM | MUX_M3_BM | channel));
+ if (ret < 0)
+ return ret;
+
+ ret = ads7871_read_reg8(spi, REG_GAIN_MUX);
+ if (ret < 0)
+ return ret;
+
+ mux_cnv = ((ret & MUX_CNV_BM) >> MUX_CNV_BV);
+ /*
+ * on 400MHz arm9 platform the conversion
+ * is already done when we do this test
+ */
+ while ((i < 2) && mux_cnv) {
+ i++;
+ ret = ads7871_read_reg8(spi, REG_GAIN_MUX);
+ if (ret < 0)
+ return ret;
+ mux_cnv = ((ret & MUX_CNV_BM) >> MUX_CNV_BV);
+ msleep_interruptible(1);
+ }
+
+ if (mux_cnv == 0) {
+ raw_val = ads7871_read_reg16(spi, REG_LS_BYTE);
+ if (raw_val < 0)
+ return raw_val;
+
+ /*
+ * Use (s16) to ensure the sign bit is preserved during the shift.
+ * Report millivolts (2.5V = 2500mV).
+ */
+ *val = ((s16)raw_val >> 2) * 2500 / 8192;
+ return 0;
+ }
+
+ return -ETIMEDOUT;
+}
+
+static const struct hwmon_channel_info * const ads7871_info[] = {
+ HWMON_CHANNEL_INFO(in,
+ HWMON_I_INPUT, HWMON_I_INPUT, HWMON_I_INPUT, HWMON_I_INPUT,
+ HWMON_I_INPUT, HWMON_I_INPUT, HWMON_I_INPUT, HWMON_I_INPUT),
+ NULL
+};
+
+static const struct hwmon_ops ads7871_hwmon_ops = {
+ .is_visible = ads7871_is_visible,
+ .read = ads7871_read,
+};
+
+static const struct hwmon_chip_info ads7871_chip_info = {
+ .ops = &ads7871_hwmon_ops,
+ .info = ads7871_info,
+};
+
+static int ads7871_probe(struct spi_device *spi)
+{
+ struct device *dev = &spi->dev;
+ int ret;
+ uint8_t val;
+ struct ads7871_data *pdata;
+ struct device *hwmon_dev;
+
+ /* Configure the SPI bus */
+ spi->mode = (SPI_MODE_0);
+ spi->bits_per_word = 8;
+ spi_setup(spi);
+
+ pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
+ if (!pdata)
+ return -ENOMEM;
+
+ pdata->spi = spi;
+
+ ads7871_write_reg8(pdata, REG_SER_CONTROL, 0);
+ ads7871_write_reg8(pdata, REG_AD_CONTROL, 0);
+
+ val = (OSC_OSCR_BM | OSC_OSCE_BM | OSC_REFE_BM | OSC_BUFE_BM);
+ ads7871_write_reg8(pdata, REG_OSC_CONTROL, val);
+ ret = ads7871_read_reg8(spi, REG_OSC_CONTROL);
+
+ dev_dbg(dev, "REG_OSC_CONTROL write:%x, read:%x\n", val, ret);
+ /*
+ * because there is no other error checking on an SPI bus
+ * we need to make sure we really have a chip
+ */
+ if (val != ret)
+ return -ENODEV;
+
+ hwmon_dev = devm_hwmon_device_register_with_info(dev, spi->modalias,
+ pdata,
+ &ads7871_chip_info,
+ NULL);
+ return PTR_ERR_OR_ZERO(hwmon_dev);
+}
+
+static struct spi_driver ads7871_driver = {
+ .driver = {
+ .name = DEVICE_NAME,
+ },
+ .probe = ads7871_probe,
+};
+
+module_spi_driver(ads7871_driver);
+
+MODULE_AUTHOR("Paul Thomas <pthomas8589@gmail.com>");
+MODULE_DESCRIPTION("TI ADS7871 A/D driver");
+MODULE_LICENSE("GPL");