Module Name: src
Committed By: hkenken
Date: Fri Nov 29 12:42:54 UTC 2019
Modified Files:
src/sys/dev/i2c: motoi2c.c
Log Message:
Add wait for stop condition.
To generate a diff of this commit:
cvs rdiff -u -r1.5 -r1.6 src/sys/dev/i2c/motoi2c.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/motoi2c.c
diff -u src/sys/dev/i2c/motoi2c.c:1.5 src/sys/dev/i2c/motoi2c.c:1.6
--- src/sys/dev/i2c/motoi2c.c:1.5 Mon Aug 5 12:21:00 2019
+++ src/sys/dev/i2c/motoi2c.c Fri Nov 29 12:42:53 2019
@@ -1,4 +1,4 @@
-/* $NetBSD: motoi2c.c,v 1.5 2019/08/05 12:21:00 hkenken Exp $ */
+/* $NetBSD: motoi2c.c,v 1.6 2019/11/29 12:42:53 hkenken Exp $ */
/*-
* Copyright (c) 2007, 2010 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: motoi2c.c,v 1.5 2019/08/05 12:21:00 hkenken Exp $");
+__KERNEL_RCSID(0, "$NetBSD: motoi2c.c,v 1.6 2019/11/29 12:42:53 hkenken Exp $");
#if defined(__arm__) || defined(__aarch64__)
#include "opt_fdt.h"
@@ -163,6 +163,24 @@ motoi2c_release_bus(void *v, int flags)
mutex_exit(&sc->sc_buslock);
}
+static int
+motoi2c_stop_wait(struct motoi2c_softc *sc)
+{
+ u_int timo;
+ int error = 0;
+
+ timo = 1000;
+ while ((I2C_READ(I2CSR) & SR_MBB) != 0 && --timo)
+ DELAY(1);
+
+ if (timo == 0) {
+ DPRINTF(("%s: timeout (sr=%#x)\n", __func__, I2C_READ(I2CSR)));
+ error = ETIMEDOUT;
+ }
+
+ return error;
+}
+
/* busy waiting for byte data transfer completion */
static int
motoi2c_busy_wait(struct motoi2c_softc *sc, uint8_t cr)
@@ -224,15 +242,9 @@ motoi2c_exec(void *v, i2c_op_t op, i2c_a
if ((cr & CR_MSTA) == 0 && (sr & SR_MBB) != 0) {
/* wait for bus becoming available */
- u_int timo = 100;
- do {
- DELAY(10);
- } while (--timo > 0 && ((sr = I2C_READ(I2CSR)) & SR_MBB) != 0);
-
- if (timo == 0) {
- DPRINTF(("%s: bus is busy (%#x)\n", __func__, sr));
+ error = motoi2c_stop_wait(sc);
+ if (error)
return ETIMEDOUT;
- }
}
/* reset interrupt and arbitration-lost flags (all others are RO) */
@@ -240,12 +252,10 @@ motoi2c_exec(void *v, i2c_op_t op, i2c_a
sr = I2C_READ(I2CSR);
/*
- * Generate start (or restart) condition
+ * Generate start condition
*/
- /* CR_RTSA is write-only and transitory */
- uint8_t rsta = (cr & CR_MSTA ? CR_RSTA : 0);
cr = CR_MEN | CR_MTX | CR_MSTA;
- I2C_WRITE(I2CCR, cr | rsta);
+ I2C_WRITE(I2CCR, cr);
DPRINTF(("%s: started: sr=%#x cr=%#x/%#x\n",
__func__, I2C_READ(I2CSR), cr, I2C_READ(I2CCR)));
@@ -339,14 +349,14 @@ motoi2c_exec(void *v, i2c_op_t op, i2c_a
cr |= CR_TXAK;
I2C_WRITE(I2CCR, cr);
} else if (i == datalen - 1 && I2C_OP_STOP_P(op)) {
- cr = CR_MEN;
+ cr = CR_MEN | CR_TXAK;
I2C_WRITE(I2CCR, cr);
}
*dataptr++ = I2C_READ(I2CDR);
}
if (datalen == 0) {
if (I2C_OP_STOP_P(op)) {
- cr = CR_MEN;
+ cr = CR_MEN | CR_TXAK;
I2C_WRITE(I2CCR, cr);
}
(void)I2C_READ(I2CDR); /* dummy read */
@@ -378,6 +388,7 @@ motoi2c_exec(void *v, i2c_op_t op, i2c_a
if (error || (cr & CR_TXAK) || ((cr & CR_MSTA) && I2C_OP_STOP_P(op))) {
cr = CR_MEN;
I2C_WRITE(I2CCR, cr);
+ motoi2c_stop_wait(sc);
DPRINTF(("%s: stopping: cr=%#x/%#x\n", __func__,
cr, I2C_READ(I2CCR)));
}
