Module Name: src
Committed By: rkujawa
Date: Tue Oct 15 10:18:49 UTC 2013
Modified Files:
src/sys/dev/i2c: mcp980x.c
Log Message:
Clean up register read and write functions, add functions for 8-bit read and
write (needed to access config register). Add sysctl knob to set resolution
from user space.
To generate a diff of this commit:
cvs rdiff -u -r1.1 -r1.2 src/sys/dev/i2c/mcp980x.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/dev/i2c/mcp980x.c
diff -u src/sys/dev/i2c/mcp980x.c:1.1 src/sys/dev/i2c/mcp980x.c:1.2
--- src/sys/dev/i2c/mcp980x.c:1.1 Mon May 6 22:04:12 2013
+++ src/sys/dev/i2c/mcp980x.c Tue Oct 15 10:18:49 2013
@@ -1,4 +1,4 @@
-/* $NetBSD: mcp980x.c,v 1.1 2013/05/06 22:04:12 rkujawa Exp $ */
+/* $NetBSD: mcp980x.c,v 1.2 2013/10/15 10:18:49 rkujawa Exp $ */
/*-
* Copyright (c) 2013 The NetBSD Foundation, Inc.
@@ -31,13 +31,12 @@
/*
* Microchip MCP9800/1/2/3 2-Wire High-Accuracy Temperature Sensor driver.
- * TODO: everything besides simple temperature read with default configuration.
*
* Note: MCP9805 is different and is supported by the sdtemp(4) driver.
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: mcp980x.c,v 1.1 2013/05/06 22:04:12 rkujawa Exp $");
+__KERNEL_RCSID(0, "$NetBSD: mcp980x.c,v 1.2 2013/10/15 10:18:49 rkujawa Exp $");
#include <sys/param.h>
#include <sys/systm.h>
@@ -45,6 +44,7 @@ __KERNEL_RCSID(0, "$NetBSD: mcp980x.c,v
#include <sys/kernel.h>
#include <sys/mutex.h>
#include <sys/endian.h>
+#include <sys/sysctl.h>
#include <sys/bus.h>
#include <dev/i2c/i2cvar.h>
@@ -59,6 +59,8 @@ struct mcp980x_softc {
i2c_tag_t sc_tag;
i2c_addr_t sc_addr;
+ int sc_res;
+
/* envsys(4) stuff */
struct sysmon_envsys *sc_sme;
envsys_data_t sc_sensor;
@@ -69,14 +71,21 @@ struct mcp980x_softc {
static int mcp980x_match(device_t, cfdata_t, void *);
static void mcp980x_attach(device_t, device_t, void *);
-/*static uint8_t mcp980x_reg_read_1(struct mcp980x_softc *sc, uint8_t);*/
-static uint16_t mcp980x_reg_read_2(struct mcp980x_softc *sc, uint8_t reg);
+static uint8_t mcp980x_reg_read_1(struct mcp980x_softc *, uint8_t);
+static uint16_t mcp980x_reg_read_2(struct mcp980x_softc *, uint8_t);
+static void mcp980x_reg_write_1(struct mcp980x_softc *, uint8_t, uint8_t);
+
+static uint8_t mcp980x_resolution_get(struct mcp980x_softc *);
+static void mcp980x_resolution_set(struct mcp980x_softc *, uint8_t);
-static uint32_t mcp980x_temperature(struct mcp980x_softc *sc);
+static uint32_t mcp980x_temperature(struct mcp980x_softc *);
static void mcp980x_envsys_register(struct mcp980x_softc *);
static void mcp980x_envsys_refresh(struct sysmon_envsys *, envsys_data_t *);
+static void mcp980x_setup_sysctl(struct mcp980x_softc *);
+static int sysctl_mcp980x_res(SYSCTLFN_ARGS);
+
CFATTACH_DECL_NEW(mcp980x, sizeof (struct mcp980x_softc),
mcp980x_match, mcp980x_attach, NULL, NULL);
@@ -103,15 +112,18 @@ mcp980x_attach(device_t parent, device_t
aprint_normal(": Microchip MCP980x Temperature Sensor\n");
+ sc->sc_res = MCP980X_CONFIG_ADC_RES_12BIT;
+ mcp980x_resolution_set(sc, sc->sc_res);
+
mutex_init(&sc->sc_lock, MUTEX_DEFAULT, IPL_NONE);
+ mcp980x_setup_sysctl(sc);
mcp980x_envsys_register(sc);
}
static uint16_t
mcp980x_reg_read_2(struct mcp980x_softc *sc, uint8_t reg)
{
- uint8_t wbuf[2];
uint16_t rv;
if (iic_acquire_bus(sc->sc_tag, I2C_F_POLL) != 0) {
@@ -119,9 +131,7 @@ mcp980x_reg_read_2(struct mcp980x_softc
return 0;
}
- wbuf[0] = reg;
-
- if (iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP, sc->sc_addr, wbuf,
+ if (iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP, sc->sc_addr, ®,
1, &rv, 2, I2C_F_POLL)) {
aprint_error_dev(sc->sc_dev, "cannot execute operation\n");
iic_release_bus(sc->sc_tag, I2C_F_POLL);
@@ -132,21 +142,17 @@ mcp980x_reg_read_2(struct mcp980x_softc
return be16toh(rv);
}
-/* Will need that later for reading config register. */
-/*
static uint8_t
mcp980x_reg_read_1(struct mcp980x_softc *sc, uint8_t reg)
{
- uint8_t rv, wbuf[2];
+ uint8_t rv;
if (iic_acquire_bus(sc->sc_tag, I2C_F_POLL) != 0) {
aprint_error_dev(sc->sc_dev, "cannot acquire bus for read\n");
return 0;
}
- wbuf[0] = reg;
-
- if (iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP, sc->sc_addr, wbuf,
+ if (iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP, sc->sc_addr, ®,
1, &rv, 1, I2C_F_POLL)) {
aprint_error_dev(sc->sc_dev, "cannot execute operation\n");
iic_release_bus(sc->sc_tag, I2C_F_POLL);
@@ -155,7 +161,49 @@ mcp980x_reg_read_1(struct mcp980x_softc
iic_release_bus(sc->sc_tag, I2C_F_POLL);
return rv;
-}*/
+}
+
+static void
+mcp980x_reg_write_1(struct mcp980x_softc *sc, uint8_t reg, uint8_t val)
+{
+ if (iic_acquire_bus(sc->sc_tag, I2C_F_POLL) != 0) {
+ aprint_error_dev(sc->sc_dev, "cannot acquire bus for write\n");
+ return;
+ }
+
+ if (iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP, sc->sc_addr, ®,
+ 1, &val, 1, I2C_F_POLL)) {
+ aprint_error_dev(sc->sc_dev, "cannot execute operation\n");
+ }
+
+ iic_release_bus(sc->sc_tag, I2C_F_POLL);
+
+}
+
+static uint8_t
+mcp980x_resolution_get(struct mcp980x_softc *sc)
+{
+ uint8_t cfg, res;
+
+ cfg = mcp980x_reg_read_1(sc, MCP980X_CONFIG);
+ res = (cfg & MCP980X_CONFIG_ADC_RES) >>
+ MCP980X_CONFIG_ADC_RES_SHIFT;
+
+ return res;
+}
+
+static void
+mcp980x_resolution_set(struct mcp980x_softc *sc, uint8_t res)
+{
+ uint8_t cfg;
+
+ /* read config register but discard resolution bits */
+ cfg = mcp980x_reg_read_1(sc, MCP980X_CONFIG) & ~MCP980X_CONFIG_ADC_RES;
+ /* set resolution bits to new value */
+ cfg |= res << MCP980X_CONFIG_ADC_RES_SHIFT;
+
+ mcp980x_reg_write_1(sc, MCP980X_CONFIG, cfg);
+}
/* Get temperature in microKelvins. */
static uint32_t
@@ -226,3 +274,59 @@ mcp980x_envsys_refresh(struct sysmon_env
mutex_exit(&sc->sc_lock);
}
+
+static void
+mcp980x_setup_sysctl(struct mcp980x_softc *sc)
+{
+ const struct sysctlnode *me = NULL, *node = NULL;
+
+ sysctl_createv(NULL, 0, NULL, &me,
+ CTLFLAG_READWRITE,
+ CTLTYPE_NODE, device_xname(sc->sc_dev), NULL,
+ NULL, 0, NULL, 0,
+ CTL_MACHDEP, CTL_CREATE, CTL_EOL);
+
+ sysctl_createv(NULL, 0, NULL, &node,
+ CTLFLAG_READWRITE | CTLFLAG_OWNDESC,
+ CTLTYPE_INT, "res", "Resolution",
+ sysctl_mcp980x_res, 1, (void *)sc, 0,
+ CTL_MACHDEP, me->sysctl_num, CTL_CREATE, CTL_EOL);
+
+}
+
+
+SYSCTL_SETUP(sysctl_lmtemp_setup, "sysctl mcp980x subtree setup")
+{
+ sysctl_createv(NULL, 0, NULL, NULL, CTLFLAG_PERMANENT,
+ CTLTYPE_NODE, "machdep", NULL, NULL, 0, NULL, 0,
+ CTL_MACHDEP, CTL_EOL);
+}
+
+
+static int
+sysctl_mcp980x_res(SYSCTLFN_ARGS)
+{
+ struct sysctlnode node = *rnode;
+ struct mcp980x_softc *sc = node.sysctl_data;
+ int newres;
+
+ if (newp) {
+ node.sysctl_data = &sc->sc_res;
+ if (sysctl_lookup(SYSCTLFN_CALL(&node)) == 0) {
+ newres = *(int *)node.sysctl_data;
+ if (newres > MCP980X_CONFIG_ADC_RES_12BIT)
+ return EINVAL;
+ sc->sc_res = (uint8_t) newres;
+ mcp980x_resolution_set(sc, sc->sc_res);
+ return 0;
+ }
+ } else {
+ sc->sc_res = mcp980x_resolution_get(sc);
+ node.sysctl_data = &sc->sc_res;
+ node.sysctl_size = 4;
+ return (sysctl_lookup(SYSCTLFN_CALL(&node)));
+ }
+
+ return EINVAL;
+}
+
