hwmon: (mcp3021) Prepare MCP3021 driver to support other chips

[firefly-linux-kernel-4.4.55.git] / drivers / hwmon / mcp3021.c

diff --git a/drivers/hwmon/mcp3021.c b/drivers/hwmon/mcp3021.c
index 5162bb95bc614dc5a4a573ce558b61aa46858cd2..d700b9271174fb1c35a553feb674a94932ad43ec 100644 (file)
--- a/drivers/hwmon/mcp3021.c
+++ b/drivers/hwmon/mcp3021.c
@@ -3,6 +3,7 @@
  *
  * Copyright (C) 2008-2009, 2012 Freescale Semiconductor, Inc.
  * Author: Mingkai Hu <Mingkai.hu@freescale.com>
+ * Reworked by Sven Schuchmann <schuchmann@schleissheimer.de>
  *
  * This driver export the value of analog input voltage to sysfs, the
  * voltage unit is mV. Through the sysfs interface, lm-sensors tool
@@ -34,16 +35,24 @@
 #define MCP3021_OUTPUT_RES     10      /* 10-bit resolution */
 #define MCP3021_OUTPUT_SCALE   4
 
+enum chips {
+       mcp3021
+};
 /*
  * Client data (each client gets its own)
  */
 struct mcp3021_data {
        struct device *hwmon_dev;
        u32 vdd;        /* device power supply */
+       u16 sar_shift;
+       u16 sar_mask;
+       u8 output_res;
+       u8 output_scale;
 };
 
 static int mcp3021_read16(struct i2c_client *client)
 {
+       struct mcp3021_data *data = i2c_get_clientdata(client);
        int ret;
        u16 reg;
        __be16 buf;
@@ -61,20 +70,20 @@ static int mcp3021_read16(struct i2c_client *client)
         * The ten-bit output code is composed of the lower 4-bit of the
         * first byte and the upper 6-bit of the second byte.
         */
-       reg = (reg >> MCP3021_SAR_SHIFT) & MCP3021_SAR_MASK;
+       reg = (reg >> data->sar_shift) & data->sar_mask;
 
        return reg;
 }
 
-static inline u16 volts_from_reg(u16 vdd, u16 val)
+static inline u16 volts_from_reg(struct mcp3021_data *data, u16 val)
 {
        if (val == 0)
                return 0;
 
-       val = val * MCP3021_OUTPUT_SCALE - MCP3021_OUTPUT_SCALE / 2;
+       val = val * data->output_scale - data->output_scale / 2;
 
-       return val * DIV_ROUND_CLOSEST(vdd,
-                       (1 << MCP3021_OUTPUT_RES) * MCP3021_OUTPUT_SCALE);
+       return val * DIV_ROUND_CLOSEST(data->vdd,
+                       (1 << data->output_res) * data->output_scale);
 }
 
 static ssize_t show_in_input(struct device *dev, struct device_attribute *attr,
@@ -88,7 +97,8 @@ static ssize_t show_in_input(struct device *dev, struct device_attribute *attr,
        if (reg < 0)
                return reg;
 
-       in_input = volts_from_reg(data->vdd, reg);
+       in_input = volts_from_reg(data, reg);
+
        return sprintf(buf, "%d\n", in_input);
 }
 
@@ -110,6 +120,15 @@ static int mcp3021_probe(struct i2c_client *client,
 
        i2c_set_clientdata(client, data);
 
+       switch (id->driver_data) {
+       case mcp3021:
+               data->sar_shift = MCP3021_SAR_SHIFT;
+               data->sar_mask = MCP3021_SAR_MASK;
+               data->output_res = MCP3021_OUTPUT_RES;
+               data->output_scale = MCP3021_OUTPUT_SCALE;
+               break;
+       }
+
        if (client->dev.platform_data) {
                data->vdd = *(u32 *)client->dev.platform_data;
                if (data->vdd > MCP3021_VDD_MAX || data->vdd < MCP3021_VDD_MIN)
@@ -145,7 +164,7 @@ static int mcp3021_remove(struct i2c_client *client)
 }
 
 static const struct i2c_device_id mcp3021_id[] = {
-       { "mcp3021", 0 },
+       { "mcp3021", mcp3021 },
        { }
 };
 MODULE_DEVICE_TABLE(i2c, mcp3021_id);