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i2c-mpc: bug fix for MPC52xx clock setting and printout 

The clock setting did not work for the MPC52xx due to a stupid bug.
Furthermore, the dev info output "clock=0" for old device trees was
misleading. This patch fixes both issues.

Signed-off-by: Wolfgang Grandegger <wg@grandegger.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
This commit is contained in:
Wolfgang Grandegger 2009-04-09 11:59:52 +02:00 committed by Ben Dooks
parent d10db3a07e
commit 1904b03430
1 changed files with 20 additions and 14 deletions
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34
drivers/i2c/busses/i2c-mpc.c
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@ -164,7 +164,7 @@ static int i2c_wait(struct mpc_i2c *i2c, unsigned timeout, int writing)
return 0; return 0;
} }
#ifdef CONFIG_PPC_52xx #ifdef CONFIG_PPC_MPC52xx
static const struct mpc_i2c_divider mpc_i2c_dividers_52xx[] = { static const struct mpc_i2c_divider mpc_i2c_dividers_52xx[] = {
{20, 0x20}, {22, 0x21}, {24, 0x22}, {26, 0x23}, {20, 0x20}, {22, 0x21}, {24, 0x22}, {26, 0x23},
{28, 0x24}, {30, 0x01}, {32, 0x25}, {34, 0x02}, {28, 0x24}, {30, 0x01}, {32, 0x25}, {34, 0x02},
@ -188,7 +188,7 @@ static const struct mpc_i2c_divider mpc_i2c_dividers_52xx[] = {
int mpc_i2c_get_fdr_52xx(struct device_node *node, u32 clock, int prescaler) int mpc_i2c_get_fdr_52xx(struct device_node *node, u32 clock, int prescaler)
{ {
const struct mpc52xx_i2c_divider *div = NULL; const struct mpc_i2c_divider *div = NULL;
unsigned int pvr = mfspr(SPRN_PVR); unsigned int pvr = mfspr(SPRN_PVR);
u32 divider; u32 divider;
int i; int i;
@ -203,7 +203,7 @@ int mpc_i2c_get_fdr_52xx(struct device_node *node, u32 clock, int prescaler)
* We want to choose an FDR/DFSR that generates an I2C bus speed that * We want to choose an FDR/DFSR that generates an I2C bus speed that
* is equal to or lower than the requested speed. * is equal to or lower than the requested speed.
*/ */
for (i = 0; i < ARRAY_SIZE(mpc52xx_i2c_dividers); i++) { for (i = 0; i < ARRAY_SIZE(mpc_i2c_dividers_52xx); i++) {
div = &mpc_i2c_dividers_52xx[i]; div = &mpc_i2c_dividers_52xx[i];
/* Old MPC5200 rev A CPUs do not support the high bits */ /* Old MPC5200 rev A CPUs do not support the high bits */
if (div->fdr & 0xc0 && pvr == 0x80822011) if (div->fdr & 0xc0 && pvr == 0x80822011)
@ -219,20 +219,23 @@ static void mpc_i2c_setclock_52xx(struct device_node *node,
struct mpc_i2c *i2c, struct mpc_i2c *i2c,
u32 clock, u32 prescaler) u32 clock, u32 prescaler)
{ {
int fdr = mpc52xx_i2c_get_fdr(node, clock, prescaler); int ret, fdr;
ret = mpc_i2c_get_fdr_52xx(node, clock, prescaler);
fdr = (ret >= 0) ? ret : 0x3f; /* backward compatibility */
if (fdr < 0)
fdr = 0x3f; /* backward compatibility */
writeb(fdr & 0xff, i2c->base + MPC_I2C_FDR); writeb(fdr & 0xff, i2c->base + MPC_I2C_FDR);
dev_info(i2c->dev, "clock %d Hz (fdr=%d)\n", clock, fdr);
if (ret >= 0)
dev_info(i2c->dev, "clock %d Hz (fdr=%d)\n", clock, fdr);
} }
#else /* !CONFIG_PPC_52xx */ #else /* !CONFIG_PPC_MPC52xx */
static void mpc_i2c_setclock_52xx(struct device_node *node, static void mpc_i2c_setclock_52xx(struct device_node *node,
struct mpc_i2c *i2c, struct mpc_i2c *i2c,
u32 clock, u32 prescaler) u32 clock, u32 prescaler)
{ {
} }
#endif /* CONFIG_PPC_52xx*/ #endif /* CONFIG_PPC_MPC52xx*/
#ifdef CONFIG_FSL_SOC #ifdef CONFIG_FSL_SOC
static const struct mpc_i2c_divider mpc_i2c_dividers_8xxx[] = { static const struct mpc_i2c_divider mpc_i2c_dividers_8xxx[] = {
@ -321,14 +324,17 @@ static void mpc_i2c_setclock_8xxx(struct device_node *node,
struct mpc_i2c *i2c, struct mpc_i2c *i2c,
u32 clock, u32 prescaler) u32 clock, u32 prescaler)
{ {
int fdr = mpc_i2c_get_fdr_8xxx(node, clock, prescaler); int ret, fdr;
ret = mpc_i2c_get_fdr_8xxx(node, clock, prescaler);
fdr = (ret >= 0) ? ret : 0x1031; /* backward compatibility */
if (fdr < 0)
fdr = 0x1031; /* backward compatibility */
writeb(fdr & 0xff, i2c->base + MPC_I2C_FDR); writeb(fdr & 0xff, i2c->base + MPC_I2C_FDR);
writeb((fdr >> 8) & 0xff, i2c->base + MPC_I2C_DFSRR); writeb((fdr >> 8) & 0xff, i2c->base + MPC_I2C_DFSRR);
dev_info(i2c->dev, "clock %d Hz (dfsrr=%d fdr=%d)\n",
clock, fdr >> 8, fdr & 0xff); if (ret >= 0)
dev_info(i2c->dev, "clock %d Hz (dfsrr=%d fdr=%d)\n",
clock, fdr >> 8, fdr & 0xff);
} }
#else /* !CONFIG_FSL_SOC */ #else /* !CONFIG_FSL_SOC */