[PATCH 2/3] i2c-mpc: add support for the MPC512x processors from Freescale
Wolfgang Grandegger
wg at grandegger.com
Mon Jan 25 23:06:36 EST 2010
Hi Wolfram,
Wolfram Sang wrote:
> Hi Wolfgang,
>
> On Mon, Jan 25, 2010 at 09:27:08AM +0100, Wolfgang Grandegger wrote:
>> From: Wolfgang Grandegger <wg at denx.de>
>>
>> The "setclock" initialization functions have been renamed to "setup"
>> because I2C interrupts must be enabled for the MPC512x. This requires
>> to handle "fsl,preserve-clocking" in a slighly different way. Also,
>> the old settings are now reported calling dev_dbg(). For the MPC512x
>> the clock setup function of the MPC52xx can be re-used.
>>
>> Signed-off-by: Wolfgang Grandegger <wg at denx.de>
>> ---
>> drivers/i2c/busses/Kconfig | 9 ++--
>> drivers/i2c/busses/i2c-mpc.c | 122 ++++++++++++++++++++++++++++++------------
>> 2 files changed, 93 insertions(+), 38 deletions(-)
>>
>> diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
>> index 5f318ce..f481f30 100644
>> --- a/drivers/i2c/busses/Kconfig
>> +++ b/drivers/i2c/busses/Kconfig
>> @@ -418,13 +418,14 @@ config I2C_IXP2000
>> instead.
>>
>> config I2C_MPC
>> - tristate "MPC107/824x/85xx/52xx/86xx"
>> + tristate "MPC107/824x/85xx/512x/52xx/86xx"
>> depends on PPC32
>> help
>> If you say yes to this option, support will be included for the
>> - built-in I2C interface on the MPC107/Tsi107/MPC8240/MPC8245 and
>> - MPC85xx/MPC8641 family processors. The driver may also work on 52xx
>> - family processors, though interrupts are known not to work.
>> + built-in I2C interface on the MPC107/Tsi107/MPC8240/MPC8245,
>> + MPC85xx/MPC8641 and MPC512x family processors. The driver may
>> + also work on 52xx family processors, though interrupts are known
>> + not to work.
>
> Opinion poll: Can we remove the "may work" sentence while we are here? It has
> worked fine for years. BTW, which interrupts are meant here (from I2C slaves?
> interrupts of the controller?)?
I first wanted to remove this sentence but as I was not sure what it's
exact meaning... Anyway, it's confusing and I would remove it.
>> This driver can also be built as a module. If so, the module
>> will be called i2c-mpc.
>> diff --git a/drivers/i2c/busses/i2c-mpc.c b/drivers/i2c/busses/i2c-mpc.c
>> index 2cb864e..70c3e5d 100644
>> --- a/drivers/i2c/busses/i2c-mpc.c
>> +++ b/drivers/i2c/busses/i2c-mpc.c
>> @@ -67,9 +67,8 @@ struct mpc_i2c_divider {
>> };
>>
>> struct mpc_i2c_data {
>> - void (*setclock)(struct device_node *node,
>> - struct mpc_i2c *i2c,
>> - u32 clock, u32 prescaler);
>> + void (*setup)(struct device_node *node, struct mpc_i2c *i2c,
>> + u32 clock, u32 prescaler);
>> u32 prescaler;
>> };
>>
>> @@ -164,7 +163,7 @@ static int i2c_wait(struct mpc_i2c *i2c, unsigned timeout, int writing)
>> return 0;
>> }
>>
>> -#ifdef CONFIG_PPC_MPC52xx
>> +#if defined(CONFIG_PPC_MPC52xx) || defined(CONFIG_PPC_MPC512x)
>> static const struct __devinitdata mpc_i2c_divider mpc_i2c_dividers_52xx[] = {
>> {20, 0x20}, {22, 0x21}, {24, 0x22}, {26, 0x23},
>> {28, 0x24}, {30, 0x01}, {32, 0x25}, {34, 0x02},
>> @@ -216,12 +215,18 @@ static int __devinit mpc_i2c_get_fdr_52xx(struct device_node *node, u32 clock,
>> return div ? (int)div->fdr : -EINVAL;
>> }
>>
>> -static void __devinit mpc_i2c_setclock_52xx(struct device_node *node,
>> - struct mpc_i2c *i2c,
>> - u32 clock, u32 prescaler)
>> +static void __devinit mpc_i2c_setup_52xx(struct device_node *node,
>> + struct mpc_i2c *i2c,
>> + u32 clock, u32 prescaler)
>> {
>> int ret, fdr;
>>
>> + if (clock == -1) {
>
> Could we use 0 for 'no_clock'? This would make the above statement simply
"0" is already used to maintain backward compatibility setting a safe
divider.
> if (!clock)
>
> and saves us using -1 with a u32.
>
>> + dev_dbg(i2c->dev, "using fdr %d\n",
>> + readb(i2c->base + MPC_I2C_FDR));
>> + return; /* preserve clocking */
>> + }
>> +
>> ret = mpc_i2c_get_fdr_52xx(node, clock, prescaler);
>> fdr = (ret >= 0) ? ret : 0x3f; /* backward compatibility */
>>
>> @@ -230,13 +235,50 @@ static void __devinit mpc_i2c_setclock_52xx(struct device_node *node,
>> if (ret >= 0)
>> dev_info(i2c->dev, "clock %d Hz (fdr=%d)\n", clock, fdr);
>> }
>> -#else /* !CONFIG_PPC_MPC52xx */
>> -static void __devinit mpc_i2c_setclock_52xx(struct device_node *node,
>> - struct mpc_i2c *i2c,
>> - u32 clock, u32 prescaler)
>> +#else /* !(CONFIG_PPC_MPC52xx || CONFIG_PPC_MPC512x) */
>> +static void __devinit mpc_i2c_setup_52xx(struct device_node *node,
>> + struct mpc_i2c *i2c,
>> + u32 clock, u32 prescaler)
>> +{
>> +}
>> +#endif /* CONFIG_PPC_MPC52xx || CONFIG_PPC_MPC512x */
>> +
>> +#ifdef CONFIG_PPC_MPC512x
>> +static void __devinit mpc_i2c_setup_512x(struct device_node *node,
>> + struct mpc_i2c *i2c,
>> + u32 clock, u32 prescaler)
>> +{
>> + struct device_node *node_ctrl;
>> + void __iomem *ctrl;
>> + const u32 *pval;
>> + u32 idx;
>> +
>> + /* Enable I2C interrupts for mpc5121 */
>> + node_ctrl = of_find_compatible_node(NULL, NULL,
>> + "fsl,mpc5121-i2c-ctrl");
>> + if (node_ctrl) {
>> + ctrl = of_iomap(node_ctrl, 0);
>> + if (ctrl) {
>> +
>> + /* Interrupt enable bits for i2c-0/1/2: bit 24/26/28 */
>> + pval = of_get_property(node, "reg", NULL);
>> + idx = (*pval & 0xff) / 0x20;
>> + setbits32(ctrl, 1 << (24 + idx * 2));
>> + iounmap(ctrl);
>> + }
>> + of_node_put(node_ctrl);
>> + }
>> +
>> + /* The clock setup for the 52xx works also fine for the 512x */
>> + mpc_i2c_setup_52xx(node, i2c, clock, prescaler);
>> +}
>> +#else /* CONFIG_PPC_MPC512x */
>> +static void __devinit mpc_i2c_setup_512x(struct device_node *node,
>> + struct mpc_i2c *i2c,
>> + u32 clock, u32 prescaler)
>> {
>> }
>> -#endif /* CONFIG_PPC_MPC52xx*/
>> +#endif /* CONFIG_PPC_MPC512x */
>>
>> #ifdef CONFIG_FSL_SOC
>> static const struct __devinitdata mpc_i2c_divider mpc_i2c_dividers_8xxx[] = {
>> @@ -322,12 +364,19 @@ static int __devinit mpc_i2c_get_fdr_8xxx(struct device_node *node, u32 clock,
>> return div ? (int)div->fdr : -EINVAL;
>> }
>>
>> -static void __devinit mpc_i2c_setclock_8xxx(struct device_node *node,
>> - struct mpc_i2c *i2c,
>> - u32 clock, u32 prescaler)
>> +static void __devinit mpc_i2c_setup_8xxx(struct device_node *node,
>> + struct mpc_i2c *i2c,
>> + u32 clock, u32 prescaler)
>> {
>> int ret, fdr;
>>
>> + if (clock == -1) {
>> + dev_dbg(i2c->dev, "using dfsrr %d, fdr %d\n",
>> + readb(i2c->base + MPC_I2C_DFSRR),
>> + readb(i2c->base + MPC_I2C_FDR));
>> + return; /* preserve clocking */
>> + }
>> +
>> ret = mpc_i2c_get_fdr_8xxx(node, clock, prescaler);
>> fdr = (ret >= 0) ? ret : 0x1031; /* backward compatibility */
>>
>> @@ -340,9 +389,9 @@ static void __devinit mpc_i2c_setclock_8xxx(struct device_node *node,
>> }
>>
>> #else /* !CONFIG_FSL_SOC */
>> -static void __devinit mpc_i2c_setclock_8xxx(struct device_node *node,
>> - struct mpc_i2c *i2c,
>> - u32 clock, u32 prescaler)
>> +static void __devinit mpc_i2c_setup_8xxx(struct device_node *node,
>> + struct mpc_i2c *i2c,
>> + u32 clock, u32 prescaler)
>> {
>> }
>> #endif /* CONFIG_FSL_SOC */
>> @@ -525,21 +574,21 @@ static int __devinit fsl_i2c_probe(struct of_device *op,
>> }
>> }
>>
>> - if (!of_get_property(op->node, "fsl,preserve-clocking", NULL)) {
>> + if (of_get_property(op->node, "fsl,preserve-clocking", NULL)) {
>> + clock = -1;
>> + } else {
>> prop = of_get_property(op->node, "clock-frequency", &plen);
>> if (prop && plen == sizeof(u32))
>> clock = *prop;
>> + }
>>
>> - if (match->data) {
>> - struct mpc_i2c_data *data =
>> - (struct mpc_i2c_data *)match->data;
>> - data->setclock(op->node, i2c, clock, data->prescaler);
>> - } else {
>> - /* Backwards compatibility */
>> - if (of_get_property(op->node, "dfsrr", NULL))
>> - mpc_i2c_setclock_8xxx(op->node, i2c,
>> - clock, 0);
>> - }
>> + if (match->data) {
>> + struct mpc_i2c_data *data = (struct mpc_i2c_data *)match->data;
>
> The cast should not be necessary.
Right.
Wolfgang.
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