Commit eff9ec95 authored by Marco Aurelio da Costa's avatar Marco Aurelio da Costa Committed by Jean Delvare

i2c-algo-pca: Add PCA9665 support

Add support for the PCA9665 I2C controller.
Signed-off-by: default avatarWolfram Sang <w.sang@pengutronix.de>
Signed-off-by: default avatarJean Delvare <khali@linux-fr.org>
parent bac3e7c2
......@@ -46,6 +46,14 @@ static int i2c_debug;
#define pca_wait(adap) adap->wait_for_completion(adap->data)
#define pca_reset(adap) adap->reset_chip(adap->data)
static void pca9665_reset(void *pd)
{
struct i2c_algo_pca_data *adap = pd;
pca_outw(adap, I2C_PCA_INDPTR, I2C_PCA_IPRESET);
pca_outw(adap, I2C_PCA_IND, 0xA5);
pca_outw(adap, I2C_PCA_IND, 0x5A);
}
/*
* Generate a start condition on the i2c bus.
*
......@@ -333,27 +341,171 @@ static const struct i2c_algorithm pca_algo = {
.functionality = pca_func,
};
static int pca_init(struct i2c_adapter *adap)
static unsigned int pca_probe_chip(struct i2c_adapter *adap)
{
static int freqs[] = {330,288,217,146,88,59,44,36};
int clock;
struct i2c_algo_pca_data *pca_data = adap->algo_data;
if (pca_data->i2c_clock > 7) {
printk(KERN_WARNING "%s: Invalid I2C clock speed selected. Trying default.\n",
adap->name);
pca_data->i2c_clock = I2C_PCA_CON_59kHz;
/* The trick here is to check if there is an indirect register
* available. If there is one, we will read the value we first
* wrote on I2C_PCA_IADR. Otherwise, we will read the last value
* we wrote on I2C_PCA_ADR
*/
pca_outw(pca_data, I2C_PCA_INDPTR, I2C_PCA_IADR);
pca_outw(pca_data, I2C_PCA_IND, 0xAA);
pca_outw(pca_data, I2C_PCA_INDPTR, I2C_PCA_ITO);
pca_outw(pca_data, I2C_PCA_IND, 0x00);
pca_outw(pca_data, I2C_PCA_INDPTR, I2C_PCA_IADR);
if (pca_inw(pca_data, I2C_PCA_IND) == 0xAA) {
printk(KERN_INFO "%s: PCA9665 detected.\n", adap->name);
return I2C_PCA_CHIP_9665;
} else {
printk(KERN_INFO "%s: PCA9564 detected.\n", adap->name);
return I2C_PCA_CHIP_9564;
}
}
static int pca_init(struct i2c_adapter *adap)
{
struct i2c_algo_pca_data *pca_data = adap->algo_data;
adap->algo = &pca_algo;
pca_reset(pca_data);
if (pca_probe_chip(adap) == I2C_PCA_CHIP_9564) {
static int freqs[] = {330, 288, 217, 146, 88, 59, 44, 36};
int clock;
if (pca_data->i2c_clock > 7) {
switch (pca_data->i2c_clock) {
case 330000:
pca_data->i2c_clock = I2C_PCA_CON_330kHz;
break;
case 288000:
pca_data->i2c_clock = I2C_PCA_CON_288kHz;
break;
case 217000:
pca_data->i2c_clock = I2C_PCA_CON_217kHz;
break;
case 146000:
pca_data->i2c_clock = I2C_PCA_CON_146kHz;
break;
case 88000:
pca_data->i2c_clock = I2C_PCA_CON_88kHz;
break;
case 59000:
pca_data->i2c_clock = I2C_PCA_CON_59kHz;
break;
case 44000:
pca_data->i2c_clock = I2C_PCA_CON_44kHz;
break;
case 36000:
pca_data->i2c_clock = I2C_PCA_CON_36kHz;
break;
default:
printk(KERN_WARNING
"%s: Invalid I2C clock speed selected."
" Using default 59kHz.\n", adap->name);
pca_data->i2c_clock = I2C_PCA_CON_59kHz;
}
} else {
printk(KERN_WARNING "%s: "
"Choosing the clock frequency based on "
"index is deprecated."
" Use the nominal frequency.\n", adap->name);
}
pca_reset(pca_data);
clock = pca_clock(pca_data);
printk(KERN_INFO "%s: Clock frequency is %dkHz\n",
adap->name, freqs[clock]);
pca_set_con(pca_data, I2C_PCA_CON_ENSIO | clock);
} else {
int clock;
int mode;
int tlow, thi;
/* Values can be found on PCA9665 datasheet section 7.3.2.6 */
int min_tlow, min_thi;
/* These values are the maximum raise and fall values allowed
* by the I2C operation mode (Standard, Fast or Fast+)
* They are used (added) below to calculate the clock dividers
* of PCA9665. Note that they are slightly different of the
* real maximum, to allow the change on mode exactly on the
* maximum clock rate for each mode
*/
int raise_fall_time;
struct i2c_algo_pca_data *pca_data = adap->algo_data;
/* Ignore the reset function from the module,
* we can use the parallel bus reset
*/
pca_data->reset_chip = pca9665_reset;
if (pca_data->i2c_clock > 1265800) {
printk(KERN_WARNING "%s: I2C clock speed too high."
" Using 1265.8kHz.\n", adap->name);
pca_data->i2c_clock = 1265800;
}
if (pca_data->i2c_clock < 60300) {
printk(KERN_WARNING "%s: I2C clock speed too low."
" Using 60.3kHz.\n", adap->name);
pca_data->i2c_clock = 60300;
}
/* To avoid integer overflow, use clock/100 for calculations */
clock = pca_clock(pca_data) / 100;
if (pca_data->i2c_clock > 10000) {
mode = I2C_PCA_MODE_TURBO;
min_tlow = 14;
min_thi = 5;
raise_fall_time = 22; /* Raise 11e-8s, Fall 11e-8s */
} else if (pca_data->i2c_clock > 4000) {
mode = I2C_PCA_MODE_FASTP;
min_tlow = 17;
min_thi = 9;
raise_fall_time = 22; /* Raise 11e-8s, Fall 11e-8s */
} else if (pca_data->i2c_clock > 1000) {
mode = I2C_PCA_MODE_FAST;
min_tlow = 44;
min_thi = 20;
raise_fall_time = 58; /* Raise 29e-8s, Fall 29e-8s */
} else {
mode = I2C_PCA_MODE_STD;
min_tlow = 157;
min_thi = 134;
raise_fall_time = 127; /* Raise 29e-8s, Fall 98e-8s */
}
/* The minimum clock that respects the thi/tlow = 134/157 is
* 64800 Hz. Below that, we have to fix the tlow to 255 and
* calculate the thi factor.
*/
if (clock < 648) {
tlow = 255;
thi = 1000000 - clock * raise_fall_time;
thi /= (I2C_PCA_OSC_PER * clock) - tlow;
} else {
tlow = (1000000 - clock * raise_fall_time) * min_tlow;
tlow /= I2C_PCA_OSC_PER * clock * (min_thi + min_tlow);
thi = tlow * min_thi / min_tlow;
}
pca_reset(pca_data);
clock = pca_clock(pca_data);
printk(KERN_INFO "%s: Clock frequency is %dkHz\n", adap->name,
freqs[clock]);
printk(KERN_INFO
"%s: Clock frequency is %dHz\n", adap->name, clock * 100);
pca_set_con(pca_data, I2C_PCA_CON_ENSIO | clock);
pca_outw(pca_data, I2C_PCA_INDPTR, I2C_PCA_IMODE);
pca_outw(pca_data, I2C_PCA_IND, mode);
pca_outw(pca_data, I2C_PCA_INDPTR, I2C_PCA_ISCLL);
pca_outw(pca_data, I2C_PCA_IND, tlow);
pca_outw(pca_data, I2C_PCA_INDPTR, I2C_PCA_ISCLH);
pca_outw(pca_data, I2C_PCA_IND, thi);
pca_set_con(pca_data, I2C_PCA_CON_ENSIO);
}
udelay(500); /* 500 us for oscilator to stabilise */
return 0;
......@@ -388,7 +540,7 @@ EXPORT_SYMBOL(i2c_pca_add_numbered_bus);
MODULE_AUTHOR("Ian Campbell <icampbell@arcom.com>, "
"Wolfram Sang <w.sang@pengutronix.de>");
MODULE_DESCRIPTION("I2C-Bus PCA9564 algorithm");
MODULE_DESCRIPTION("I2C-Bus PCA9564/PCA9665 algorithm");
MODULE_LICENSE("GPL");
module_param(i2c_debug, int, 0);
......@@ -617,12 +617,12 @@ config I2C_ELEKTOR
will be called i2c-elektor.
config I2C_PCA_ISA
tristate "PCA9564 on an ISA bus"
tristate "PCA9564/PCA9665 on an ISA bus"
depends on ISA
select I2C_ALGOPCA
default n
help
This driver supports ISA boards using the Philips PCA9564
This driver supports ISA boards using the Philips PCA9564/PCA9665
parallel bus to I2C bus controller.
This driver can also be built as a module. If so, the module
......@@ -634,11 +634,11 @@ config I2C_PCA_ISA
time). If unsure, say N.
config I2C_PCA_PLATFORM
tristate "PCA9564 as platform device"
tristate "PCA9564/PCA9665 as platform device"
select I2C_ALGOPCA
default n
help
This driver supports a memory mapped Philips PCA9564
This driver supports a memory mapped Philips PCA9564/PCA9665
parallel bus to I2C bus controller.
This driver can also be built as a module. If so, the module
......
......@@ -41,7 +41,7 @@ static int irq = -1;
/* Data sheet recommends 59kHz for 100kHz operation due to variation
* in the actual clock rate */
static int clock = I2C_PCA_CON_59kHz;
static int clock = 59000;
static wait_queue_head_t pca_wait;
......@@ -103,7 +103,7 @@ static struct i2c_algo_pca_data pca_isa_data = {
static struct i2c_adapter pca_isa_ops = {
.owner = THIS_MODULE,
.algo_data = &pca_isa_data,
.name = "PCA9564 ISA Adapter",
.name = "PCA9564/PCA9665 ISA Adapter",
.timeout = 100,
};
......@@ -196,7 +196,7 @@ static void __exit pca_isa_exit(void)
}
MODULE_AUTHOR("Ian Campbell <icampbell@arcom.com>");
MODULE_DESCRIPTION("ISA base PCA9564 driver");
MODULE_DESCRIPTION("ISA base PCA9564/PCA9665 driver");
MODULE_LICENSE("GPL");
module_param(base, ulong, 0);
......@@ -205,7 +205,13 @@ MODULE_PARM_DESC(base, "I/O base address");
module_param(irq, int, 0);
MODULE_PARM_DESC(irq, "IRQ");
module_param(clock, int, 0);
MODULE_PARM_DESC(clock, "Clock rate as described in table 1 of PCA9564 datasheet");
MODULE_PARM_DESC(clock, "Clock rate in hertz.\n\t\t"
"For PCA9564: 330000,288000,217000,146000,"
"88000,59000,44000,36000\n"
"\t\tFor PCA9665:\tStandard: 60300 - 100099\n"
"\t\t\t\tFast: 100100 - 400099\n"
"\t\t\t\tFast+: 400100 - 10000099\n"
"\t\t\t\tTurbo: Up to 1265800");
module_init(pca_isa_init);
module_exit(pca_isa_exit);
......@@ -172,8 +172,9 @@ static int __devinit i2c_pca_pf_probe(struct platform_device *pdev)
i2c->adap.nr = pdev->id >= 0 ? pdev->id : 0;
i2c->adap.owner = THIS_MODULE;
snprintf(i2c->adap.name, sizeof(i2c->adap.name), "PCA9564 at 0x%08lx",
(unsigned long) res->start);
snprintf(i2c->adap.name, sizeof(i2c->adap.name),
"PCA9564/PCA9665 at 0x%08lx",
(unsigned long) res->start);
i2c->adap.algo_data = &i2c->algo_data;
i2c->adap.dev.parent = &pdev->dev;
i2c->adap.timeout = platform_data->timeout;
......@@ -246,7 +247,7 @@ e_remap:
e_alloc:
release_mem_region(res->start, res_len(res));
e_print:
printk(KERN_ERR "Registering PCA9564 FAILED! (%d)\n", ret);
printk(KERN_ERR "Registering PCA9564/PCA9665 FAILED! (%d)\n", ret);
return ret;
}
......@@ -290,7 +291,7 @@ static void __exit i2c_pca_pf_exit(void)
}
MODULE_AUTHOR("Wolfram Sang <w.sang@pengutronix.de>");
MODULE_DESCRIPTION("I2C-PCA9564 platform driver");
MODULE_DESCRIPTION("I2C-PCA9564/PCA9665 platform driver");
MODULE_LICENSE("GPL");
module_init(i2c_pca_pf_init);
......
#ifndef _LINUX_I2C_ALGO_PCA_H
#define _LINUX_I2C_ALGO_PCA_H
/* Clock speeds for the bus */
/* Chips known to the pca algo */
#define I2C_PCA_CHIP_9564 0x00
#define I2C_PCA_CHIP_9665 0x01
/* Internal period for PCA9665 oscilator */
#define I2C_PCA_OSC_PER 3 /* e10-8s */
/* Clock speeds for the bus for PCA9564*/
#define I2C_PCA_CON_330kHz 0x00
#define I2C_PCA_CON_288kHz 0x01
#define I2C_PCA_CON_217kHz 0x02
......@@ -18,6 +25,26 @@
#define I2C_PCA_ADR 0x02 /* OWN ADR Read/Write */
#define I2C_PCA_CON 0x03 /* CONTROL Read/Write */
/* PCA9665 registers */
#define I2C_PCA_INDPTR 0x00 /* INDIRECT Pointer Write Only */
#define I2C_PCA_IND 0x02 /* INDIRECT Read/Write */
/* PCA9665 indirect registers */
#define I2C_PCA_ICOUNT 0x00 /* Byte Count for buffered mode */
#define I2C_PCA_IADR 0x01 /* OWN ADR */
#define I2C_PCA_ISCLL 0x02 /* SCL LOW period */
#define I2C_PCA_ISCLH 0x03 /* SCL HIGH period */
#define I2C_PCA_ITO 0x04 /* TIMEOUT */
#define I2C_PCA_IPRESET 0x05 /* Parallel bus reset */
#define I2C_PCA_IMODE 0x06 /* I2C Bus mode */
/* PCA9665 I2C bus mode */
#define I2C_PCA_MODE_STD 0x00 /* Standard mode */
#define I2C_PCA_MODE_FAST 0x01 /* Fast mode */
#define I2C_PCA_MODE_FASTP 0x02 /* Fast Plus mode */
#define I2C_PCA_MODE_TURBO 0x03 /* Turbo mode */
#define I2C_PCA_CON_AA 0x80 /* Assert Acknowledge */
#define I2C_PCA_CON_ENSIO 0x40 /* Enable */
#define I2C_PCA_CON_STA 0x20 /* Start */
......@@ -31,7 +58,9 @@ struct i2c_algo_pca_data {
int (*read_byte) (void *data, int reg);
int (*wait_for_completion) (void *data);
void (*reset_chip) (void *data);
/* i2c_clock values are defined in linux/i2c-algo-pca.h */
/* For PCA9564, use one of the predefined frequencies:
* 330000, 288000, 217000, 146000, 88000, 59000, 44000, 36000
* For PCA9665, use the frequency you want here. */
unsigned int i2c_clock;
};
......
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