[src/trunk]: src/sys/arch/sparc64/dev Don't read from the chip when matching,...

[jdc <jdc%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/9109943766a1
branches:  trunk
changeset: 978869:9109943766a1
user:      jdc <jdc%NetBSD.org@localhost>
date:      Sun Dec 06 10:06:15 2020 +0000

description:
Don't read from the chip when matching, fail the attach instead (requested
by jmcneill).  Reverts previous.
While here, handle errors attaching sysmon and acquiring the iic bus lock.

diffstat:

 sys/arch/sparc64/dev/pcf8591_envctrl.c |  41 ++++++++++++---------------------
 1 files changed, 15 insertions(+), 26 deletions(-)

diffs (94 lines):

diff -r 43841a90f207 -r 9109943766a1 sys/arch/sparc64/dev/pcf8591_envctrl.c
--- a/sys/arch/sparc64/dev/pcf8591_envctrl.c    Sun Dec 06 09:03:29 2020 +0000
+++ b/sys/arch/sparc64/dev/pcf8591_envctrl.c    Sun Dec 06 10:06:15 2020 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: pcf8591_envctrl.c,v 1.12 2020/12/05 15:08:21 jdc Exp $ */
+/*     $NetBSD: pcf8591_envctrl.c,v 1.13 2020/12/06 10:06:15 jdc Exp $ */
 /*     $OpenBSD: pcf8591_envctrl.c,v 1.6 2007/10/25 21:17:20 kettenis Exp $ */
 
 /*
@@ -19,7 +19,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: pcf8591_envctrl.c,v 1.12 2020/12/05 15:08:21 jdc Exp $");
+__KERNEL_RCSID(0, "$NetBSD: pcf8591_envctrl.c,v 1.13 2020/12/06 10:06:15 jdc Exp $");
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -99,28 +99,10 @@
 ecadc_match(device_t parent, cfdata_t cf, void *aux)
 {
        struct i2c_attach_args *ia = aux;
-       struct ecadc_softc sc;
        int match_result;
-       u_int8_t junk;
-
-       if (!iic_use_direct_match(ia, cf, compat_data, &match_result))
-               return 0;
 
-       /* Try a read so that we don't match on optional components */
-       if (match_result) {
-               sc.sc_tag = ia->ia_tag;
-               sc.sc_addr = ia->ia_addr;
-
-               iic_acquire_bus(sc.sc_tag, 0);
-               if (iic_exec(sc.sc_tag, I2C_OP_READ_WITH_STOP, sc.sc_addr,
-                   NULL, 0, &junk, 1, 0)) {
-                       iic_release_bus(sc.sc_tag, 0);
-                       return 0;
-               } else {
-                       iic_release_bus(sc.sc_tag, 0);
-                       return match_result;
-               }
-       }
+       if (iic_use_direct_match(ia, cf, compat_data, &match_result))
+               return match_result;
 
        /* This driver is direct-config only. */
 
@@ -232,10 +214,10 @@
 
        iic_acquire_bus(sc->sc_tag, 0);
 
-       /* Try a read now, so we can fail if it doesn't work */
+       /* Try a read now, so we can fail if this component isn't present */
        if (iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP, sc->sc_addr,
            NULL, 0, junk, sc->sc_nchan + 1, 0)) {
-               aprint_error(": read failed\n");
+               aprint_normal(": read failed\n");
                iic_release_bus(sc->sc_tag, 0);
                return;
        }
@@ -259,6 +241,7 @@
                aprint_error_dev(self, "error %d registering with sysmon\n",
                        error);
                sysmon_envsys_destroy(sc->sc_sme);
+               sc->sc_sme = NULL;
                return;
        }
        
@@ -296,7 +279,8 @@
        u_int8_t ctrl = PCF8591_CTRL_CH0 | PCF8591_CTRL_AUTOINC |
            PCF8591_CTRL_OSCILLATOR;
 
-       iic_acquire_bus(sc->sc_tag, 0);
+       if (iic_acquire_bus(sc->sc_tag, 0))
+               return;
        if (iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP, sc->sc_addr,
            &ctrl, 1, NULL, 0, 0)) {
                iic_release_bus(sc->sc_tag, 0);
@@ -386,7 +370,12 @@
        int ret;
 
        ctrl |= chan;
-       iic_acquire_bus(sc->sc_tag, 0);
+       ret = iic_acquire_bus(sc->sc_tag, 0);
+       if (ret) {
+               aprint_error_dev(sc->sc_dev,
+                   "error acquiring i2c bus (ch %d)\n", chan);
+               return ret;
+       }
        ret = iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP, sc->sc_addr,
            &ctrl, 1, &val, 1, 0);
        if (ret)