diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2009-03-28 14:04:53 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2009-03-28 14:04:53 -0700 |
commit | 07d43ba98621f08e252a48c96b258b4d572b0257 (patch) | |
tree | c5dd8be6b2032b02fb2a27a91b02a55d54ed702d | |
parent | 0fe41b8982001cd14ee2c77cd776735a5024e98b (diff) | |
parent | 09b8ce0a691d8e76f14a16ac6cbfde899f6c68e3 (diff) |
Merge branch 'i2c-for-linus' of git://jdelvare.pck.nerim.net/jdelvare-2.6
* 'i2c-for-linus' of git://jdelvare.pck.nerim.net/jdelvare-2.6:
i2c-core: Some style cleanups
i2c-piix4: Add support for the Broadcom HT1100 chipset
i2c-piix4: Add support to SB800 SMBus changes
i2c-pca-platform: Use defaults if no platform_data given
i2c-algo-pca: Use timeout for checking the state machine
i2c-algo-pca: Rework waiting for a free bus
i2c-algo-pca: Add PCA9665 support
i2c: Adapt debug macros for KERN_* constants
i2c-davinci: Fix timeout handling
i2c: Adapter timeout is in jiffies
i2c: Set a default timeout value for all adapters
i2c: Add missing KERN_* constants to printks
i2c-algo-pcf: Handle timeout correctly
i2c-algo-pcf: Style cleanups
eeprom/at24: Remove EXPERIMENTAL
i2c-nforce2: Add support for MCP67, MCP73, MCP78S and MCP79
i2c: Clarify which clients are auto-removed
i2c: Let checkpatch shout on users of the legacy model
i2c: Document the different ways to instantiate i2c devices
26 files changed, 746 insertions, 276 deletions
diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt index 02ea3773535..7907586c6e0 100644 --- a/Documentation/feature-removal-schedule.txt +++ b/Documentation/feature-removal-schedule.txt @@ -340,7 +340,8 @@ Who: Krzysztof Piotr Oledzki <ole@ans.pl> --------------------------- What: i2c_attach_client(), i2c_detach_client(), i2c_driver->detach_client() -When: 2.6.29 (ideally) or 2.6.30 (more likely) +When: 2.6.30 +Check: i2c_attach_client i2c_detach_client Why: Deprecated by the new (standard) device driver binding model. Use i2c_driver->probe() and ->remove() instead. Who: Jean Delvare <khali@linux-fr.org> diff --git a/Documentation/i2c/busses/i2c-nforce2 b/Documentation/i2c/busses/i2c-nforce2 index fae3495bcba..9698c396b83 100644 --- a/Documentation/i2c/busses/i2c-nforce2 +++ b/Documentation/i2c/busses/i2c-nforce2 @@ -7,10 +7,14 @@ Supported adapters: * nForce3 250Gb MCP 10de:00E4 * nForce4 MCP 10de:0052 * nForce4 MCP-04 10de:0034 - * nForce4 MCP51 10de:0264 - * nForce4 MCP55 10de:0368 - * nForce4 MCP61 10de:03EB - * nForce4 MCP65 10de:0446 + * nForce MCP51 10de:0264 + * nForce MCP55 10de:0368 + * nForce MCP61 10de:03EB + * nForce MCP65 10de:0446 + * nForce MCP67 10de:0542 + * nForce MCP73 10de:07D8 + * nForce MCP78S 10de:0752 + * nForce MCP79 10de:0AA2 Datasheet: not publicly available, but seems to be similar to the AMD-8111 SMBus 2.0 adapter. diff --git a/Documentation/i2c/busses/i2c-piix4 b/Documentation/i2c/busses/i2c-piix4 index ef1efa79b1d..f889481762b 100644 --- a/Documentation/i2c/busses/i2c-piix4 +++ b/Documentation/i2c/busses/i2c-piix4 @@ -4,7 +4,7 @@ Supported adapters: * Intel 82371AB PIIX4 and PIIX4E * Intel 82443MX (440MX) Datasheet: Publicly available at the Intel website - * ServerWorks OSB4, CSB5, CSB6 and HT-1000 southbridges + * ServerWorks OSB4, CSB5, CSB6, HT-1000 and HT-1100 southbridges Datasheet: Only available via NDA from ServerWorks * ATI IXP200, IXP300, IXP400, SB600, SB700 and SB800 southbridges Datasheet: Not publicly available diff --git a/Documentation/i2c/instantiating-devices b/Documentation/i2c/instantiating-devices new file mode 100644 index 00000000000..b55ce57a84d --- /dev/null +++ b/Documentation/i2c/instantiating-devices @@ -0,0 +1,167 @@ +How to instantiate I2C devices +============================== + +Unlike PCI or USB devices, I2C devices are not enumerated at the hardware +level. Instead, the software must know which devices are connected on each +I2C bus segment, and what address these devices are using. For this +reason, the kernel code must instantiate I2C devices explicitly. There are +several ways to achieve this, depending on the context and requirements. + + +Method 1: Declare the I2C devices by bus number +----------------------------------------------- + +This method is appropriate when the I2C bus is a system bus as is the case +for many embedded systems. On such systems, each I2C bus has a number +which is known in advance. It is thus possible to pre-declare the I2C +devices which live on this bus. This is done with an array of struct +i2c_board_info which is registered by calling i2c_register_board_info(). + +Example (from omap2 h4): + +static struct i2c_board_info __initdata h4_i2c_board_info[] = { + { + I2C_BOARD_INFO("isp1301_omap", 0x2d), + .irq = OMAP_GPIO_IRQ(125), + }, + { /* EEPROM on mainboard */ + I2C_BOARD_INFO("24c01", 0x52), + .platform_data = &m24c01, + }, + { /* EEPROM on cpu card */ + I2C_BOARD_INFO("24c01", 0x57), + .platform_data = &m24c01, + }, +}; + +static void __init omap_h4_init(void) +{ + (...) + i2c_register_board_info(1, h4_i2c_board_info, + ARRAY_SIZE(h4_i2c_board_info)); + (...) +} + +The above code declares 3 devices on I2C bus 1, including their respective +addresses and custom data needed by their drivers. When the I2C bus in +question is registered, the I2C devices will be instantiated automatically +by i2c-core. + +The devices will be automatically unbound and destroyed when the I2C bus +they sit on goes away (if ever.) + + +Method 2: Instantiate the devices explicitly +-------------------------------------------- + +This method is appropriate when a larger device uses an I2C bus for +internal communication. A typical case is TV adapters. These can have a +tuner, a video decoder, an audio decoder, etc. usually connected to the +main chip by the means of an I2C bus. You won't know the number of the I2C +bus in advance, so the method 1 described above can't be used. Instead, +you can instantiate your I2C devices explicitly. This is done by filling +a struct i2c_board_info and calling i2c_new_device(). + +Example (from the sfe4001 network driver): + +static struct i2c_board_info sfe4001_hwmon_info = { + I2C_BOARD_INFO("max6647", 0x4e), +}; + +int sfe4001_init(struct efx_nic *efx) +{ + (...) + efx->board_info.hwmon_client = + i2c_new_device(&efx->i2c_adap, &sfe4001_hwmon_info); + + (...) +} + +The above code instantiates 1 I2C device on the I2C bus which is on the +network adapter in question. + +A variant of this is when you don't know for sure if an I2C device is +present or not (for example for an optional feature which is not present +on cheap variants of a board but you have no way to tell them apart), or +it may have different addresses from one board to the next (manufacturer +changing its design without notice). In this case, you can call +i2c_new_probed_device() instead of i2c_new_device(). + +Example (from the pnx4008 OHCI driver): + +static const unsigned short normal_i2c[] = { 0x2c, 0x2d, I2C_CLIENT_END }; + +static int __devinit usb_hcd_pnx4008_probe(struct platform_device *pdev) +{ + (...) + struct i2c_adapter *i2c_adap; + struct i2c_board_info i2c_info; + + (...) + i2c_adap = i2c_get_adapter(2); + memset(&i2c_info, 0, sizeof(struct i2c_board_info)); + strlcpy(i2c_info.name, "isp1301_pnx", I2C_NAME_SIZE); + isp1301_i2c_client = i2c_new_probed_device(i2c_adap, &i2c_info, + normal_i2c); + i2c_put_adapter(i2c_adap); + (...) +} + +The above code instantiates up to 1 I2C device on the I2C bus which is on +the OHCI adapter in question. It first tries at address 0x2c, if nothing +is found there it tries address 0x2d, and if still nothing is found, it +simply gives up. + +The driver which instantiated the I2C device is responsible for destroying +it on cleanup. This is done by calling i2c_unregister_device() on the +pointer that was earlier returned by i2c_new_device() or +i2c_new_probed_device(). + + +Method 3: Probe an I2C bus for certain devices +---------------------------------------------- + +Sometimes you do not have enough information about an I2C device, not even +to call i2c_new_probed_device(). The typical case is hardware monitoring +chips on PC mainboards. There are several dozen models, which can live +at 25 different addresses. Given the huge number of mainboards out there, +it is next to impossible to build an exhaustive list of the hardware +monitoring chips being used. Fortunately, most of these chips have +manufacturer and device ID registers, so they can be identified by +probing. + +In that case, I2C devices are neither declared nor instantiated +explicitly. Instead, i2c-core will probe for such devices as soon as their +drivers are loaded, and if any is found, an I2C device will be +instantiated automatically. In order to prevent any misbehavior of this +mechanism, the following restrictions apply: +* The I2C device driver must implement the detect() method, which + identifies a supported device by reading from arbitrary registers. +* Only buses which are likely to have a supported device and agree to be + probed, will be probed. For example this avoids probing for hardware + monitoring chips on a TV adapter. + +Example: +See lm90_driver and lm90_detect() in drivers/hwmon/lm90.c + +I2C devices instantiated as a result of such a successful probe will be +destroyed automatically when the driver which detected them is removed, +or when the underlying I2C bus is itself destroyed, whichever happens +first. + +Those of you familiar with the i2c subsystem of 2.4 kernels and early 2.6 +kernels will find out that this method 3 is essentially similar to what +was done there. Two significant differences are: +* Probing is only one way to instantiate I2C devices now, while it was the + only way back then. Where possible, methods 1 and 2 should be preferred. + Method 3 should only be used when there is no other way, as it can have + undesirable side effects. +* I2C buses must now explicitly say which I2C driver classes can probe + them (by the means of the class bitfield), while all I2C buses were + probed by default back then. The default is an empty class which means + that no probing happens. The purpose of the class bitfield is to limit + the aforementioned undesirable side effects. + +Once again, method 3 should be avoided wherever possible. Explicit device +instantiation (methods 1 and 2) is much preferred for it is safer and +faster. diff --git a/Documentation/i2c/writing-clients b/Documentation/i2c/writing-clients index 6b9af7d479c..c1a06f989cf 100644 --- a/Documentation/i2c/writing-clients +++ b/Documentation/i2c/writing-clients @@ -207,15 +207,26 @@ You simply have to define a detect callback which will attempt to identify supported devices (returning 0 for supported ones and -ENODEV for unsupported ones), a list of addresses to probe, and a device type (or class) so that only I2C buses which may have that type of device -connected (and not otherwise enumerated) will be probed. The i2c -core will then call you back as needed and will instantiate a device -for you for every successful detection. +connected (and not otherwise enumerated) will be probed. For example, +a driver for a hardware monitoring chip for which auto-detection is +needed would set its class to I2C_CLASS_HWMON, and only I2C adapters +with a class including I2C_CLASS_HWMON would be probed by this driver. +Note that the absence of matching classes does not prevent the use of +a device of that type on the given I2C adapter. All it prevents is +auto-detection; explicit instantiation of devices is still possible. Note that this mechanism is purely optional and not suitable for all devices. You need some reliable way to identify the supported devices (typically using device-specific, dedicated identification registers), otherwise misdetections are likely to occur and things can get wrong -quickly. +quickly. Keep in mind that the I2C protocol doesn't include any +standard way to detect the presence of a chip at a given address, let +alone a standard way to identify devices. Even worse is the lack of +semantics associated to bus transfers, which means that the same +transfer can be seen as a read operation by a chip and as a write +operation by another chip. For these reasons, explicit device +instantiation should always be preferred to auto-detection where +possible. Device Deletion diff --git a/arch/sh/boards/board-sh7785lcr.c b/arch/sh/boards/board-sh7785lcr.c index 94c0296bc35..6f94f17adc4 100644 --- a/arch/sh/boards/board-sh7785lcr.c +++ b/arch/sh/boards/board-sh7785lcr.c @@ -229,7 +229,7 @@ static struct resource i2c_resources[] = { static struct i2c_pca9564_pf_platform_data i2c_platform_data = { .gpio = 0, .i2c_clock_speed = I2C_PCA_CON_330kHz, - .timeout = 100, + .timeout = HZ, }; static struct platform_device i2c_device = { diff --git a/drivers/i2c/algos/i2c-algo-bit.c b/drivers/i2c/algos/i2c-algo-bit.c index eb8f72ca02f..d420cc5f563 100644 --- a/drivers/i2c/algos/i2c-algo-bit.c +++ b/drivers/i2c/algos/i2c-algo-bit.c @@ -604,9 +604,7 @@ static int i2c_bit_prepare_bus(struct i2c_adapter *adap) /* register new adapter to i2c module... */ adap->algo = &i2c_bit_algo; - - adap->timeout = 100; /* default values, should */ - adap->retries = 3; /* be replaced by defines */ + adap->retries = 3; return 0; } diff --git a/drivers/i2c/algos/i2c-algo-pca.c b/drivers/i2c/algos/i2c-algo-pca.c index d50b329a3c9..f68e5f8e23e 100644 --- a/drivers/i2c/algos/i2c-algo-pca.c +++ b/drivers/i2c/algos/i2c-algo-pca.c @@ -22,14 +22,18 @@ #include <linux/module.h> #include <linux/moduleparam.h> #include <linux/delay.h> +#include <linux/jiffies.h> #include <linux/init.h> #include <linux/errno.h> #include <linux/i2c.h> #include <linux/i2c-algo-pca.h> -#define DEB1(fmt, args...) do { if (i2c_debug>=1) printk(fmt, ## args); } while(0) -#define DEB2(fmt, args...) do { if (i2c_debug>=2) printk(fmt, ## args); } while(0) -#define DEB3(fmt, args...) do { if (i2c_debug>=3) printk(fmt, ## args); } while(0) +#define DEB1(fmt, args...) do { if (i2c_debug >= 1) \ + printk(KERN_DEBUG fmt, ## args); } while (0) +#define DEB2(fmt, args...) do { if (i2c_debug >= 2) \ + printk(KERN_DEBUG fmt, ## args); } while (0) +#define DEB3(fmt, args...) do { if (i2c_debug >= 3) \ + printk(KERN_DEBUG fmt, ## args); } while (0) static int i2c_debug; @@ -43,19 +47,27 @@ 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. * * returns after the start condition has occurred */ -static void pca_start(struct i2c_algo_pca_data *adap) +static int pca_start(struct i2c_algo_pca_data *adap) { int sta = pca_get_con(adap); DEB2("=== START\n"); sta |= I2C_PCA_CON_STA; sta &= ~(I2C_PCA_CON_STO|I2C_PCA_CON_SI); pca_set_con(adap, sta); - pca_wait(adap); + return pca_wait(adap); } /* @@ -63,14 +75,14 @@ static void pca_start(struct i2c_algo_pca_data *adap) * * return after the repeated start condition has occurred */ -static void pca_repeated_start(struct i2c_algo_pca_data *adap) +static int pca_repeated_start(struct i2c_algo_pca_data *adap) { int sta = pca_get_con(adap); DEB2("=== REPEATED START\n"); sta |= I2C_PCA_CON_STA; sta &= ~(I2C_PCA_CON_STO|I2C_PCA_CON_SI); pca_set_con(adap, sta); - pca_wait(adap); + return pca_wait(adap); } /* @@ -96,7 +108,7 @@ static void pca_stop(struct i2c_algo_pca_data *adap) * * returns after the address has been sent */ -static void pca_address(struct i2c_algo_pca_data *adap, +static int pca_address(struct i2c_algo_pca_data *adap, struct i2c_msg *msg) { int sta = pca_get_con(adap); @@ -113,7 +125,7 @@ static void pca_address(struct i2c_algo_pca_data *adap, sta &= ~(I2C_PCA_CON_STO|I2C_PCA_CON_STA|I2C_PCA_CON_SI); pca_set_con(adap, sta); - pca_wait(adap); + return pca_wait(adap); } /* @@ -121,7 +133,7 @@ static void pca_address(struct i2c_algo_pca_data *adap, * * Returns after the byte has been transmitted */ -static void pca_tx_byte(struct i2c_algo_pca_data *adap, +static int pca_tx_byte(struct i2c_algo_pca_data *adap, __u8 b) { int sta = pca_get_con(adap); @@ -131,7 +143,7 @@ static void pca_tx_byte(struct i2c_algo_pca_data *adap, sta &= ~(I2C_PCA_CON_STO|I2C_PCA_CON_STA|I2C_PCA_CON_SI); pca_set_con(adap, sta); - pca_wait(adap); + return pca_wait(adap); } /* @@ -151,7 +163,7 @@ static void pca_rx_byte(struct i2c_algo_pca_data *adap, * * Returns after next byte has arrived. */ -static void pca_rx_ack(struct i2c_algo_pca_data *adap, +static int pca_rx_ack(struct i2c_algo_pca_data *adap, int ack) { int sta = pca_get_con(adap); @@ -162,7 +174,7 @@ static void pca_rx_ack(struct i2c_algo_pca_data *adap, sta |= I2C_PCA_CON_AA; pca_set_con(adap, sta); - pca_wait(adap); + return pca_wait(adap); } static int pca_xfer(struct i2c_adapter *i2c_adap, @@ -175,14 +187,17 @@ static int pca_xfer(struct i2c_adapter *i2c_adap, int numbytes = 0; int state; int ret; - int timeout = i2c_adap->timeout; - - while ((state = pca_status(adap)) != 0xf8 && timeout--) { - msleep(10); - } - if (state != 0xf8) { - dev_dbg(&i2c_adap->dev, "bus is not idle. status is %#04x\n", state); - return -EAGAIN; + int completed = 1; + unsigned long timeout = jiffies + i2c_adap->timeout; + + while (pca_status(adap) != 0xf8) { + if (time_before(jiffies, timeout)) { + msleep(10); + } else { + dev_dbg(&i2c_adap->dev, "bus is not idle. status is " + "%#04x\n", state); + return -EAGAIN; + } } DEB1("{{{ XFER %d messages\n", num); @@ -218,18 +233,19 @@ static int pca_xfer(struct i2c_adapter *i2c_adap, switch (state) { case 0xf8: /* On reset or stop the bus is idle */ - pca_start(adap); + completed = pca_start(adap); break; case 0x08: /* A START condition has been transmitted */ case 0x10: /* A repeated start condition has been transmitted */ - pca_address(adap, msg); + completed = pca_address(adap, msg); break; case 0x18: /* SLA+W has been transmitted; ACK has been received */ case 0x28: /* Data byte in I2CDAT has been transmitted; ACK has been received */ if (numbytes < msg->len) { - pca_tx_byte(adap, msg->buf[numbytes]); + completed = pca_tx_byte(adap, + msg->buf[numbytes]); numbytes++; break; } @@ -237,7 +253,7 @@ static int pca_xfer(struct i2c_adapter *i2c_adap, if (curmsg == num) pca_stop(adap); else - pca_repeated_start(adap); + completed = pca_repeated_start(adap); break; case 0x20: /* SLA+W has been transmitted; NOT ACK has been received */ @@ -246,21 +262,22 @@ static int pca_xfer(struct i2c_adapter *i2c_adap, goto out; case 0x40: /* SLA+R has been transmitted; ACK has been received */ - pca_rx_ack(adap, msg->len > 1); + completed = pca_rx_ack(adap, msg->len > 1); break; case 0x50: /* Data bytes has been received; ACK has been returned */ if (numbytes < msg->len) { pca_rx_byte(adap, &msg->buf[numbytes], 1); numbytes++; - pca_rx_ack(adap, numbytes < msg->len - 1); + completed = pca_rx_ack(adap, + numbytes < msg->len - 1); break; } curmsg++; numbytes = 0; if (curmsg == num) pca_stop(adap); else - pca_repeated_start(adap); + completed = pca_repeated_start(adap); break; case 0x48: /* SLA+R has been transmitted; NOT ACK has been received */ @@ -283,7 +300,7 @@ static int pca_xfer(struct i2c_adapter *i2c_adap, if (curmsg == num) pca_stop(adap); else - pca_repeated_start(adap); + completed = pca_repeated_start(adap); } else { DEB2("NOT ACK sent after data byte received. " "Not final byte. numbytes %d. len %d\n", @@ -309,11 +326,13 @@ static int pca_xfer(struct i2c_adapter *i2c_adap, break; } + if (!completed) + goto out; } ret = curmsg; out: - DEB1(KERN_CRIT "}}} transfered %d/%d messages. " + DEB1("}}} transfered %d/%d messages. " "status is %#04x. control is %#04x\n", curmsg, num, pca_status(adap), pca_get_con(adap)); @@ -330,26 +349,171 @@ 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; + } - clock = pca_clock(pca_data); - DEB1(KERN_INFO "%s: Clock frequency is %dkHz\n", adap->name, freqs[clock]); + /* 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_set_con(pca_data, I2C_PCA_CON_ENSIO | clock); + pca_reset(pca_data); + + printk(KERN_INFO + "%s: Clock frequency is %dHz\n", adap->name, clock * 100); + + 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; @@ -384,7 +548,7 @@ 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); diff --git a/drivers/i2c/algos/i2c-algo-pcf.c b/drivers/i2c/algos/i2c-algo-pcf.c index 3e01992230b..7ce75775ec7 100644 --- a/drivers/i2c/algos/i2c-algo-pcf.c +++ b/drivers/i2c/algos/i2c-algo-pcf.c @@ -1,31 +1,30 @@ -/* ------------------------------------------------------------------------- */ -/* i2c-algo-pcf.c i2c driver algorithms for PCF8584 adapters */ -/* ------------------------------------------------------------------------- */ -/* Copyright (C) 1995-1997 Simon G. Vogl - 1998-2000 Hans Berglund - - This program is free software; you can redistribute it and/or modify - it under the terms of the GNU General Public License as published by - the Free Software Foundation; either version 2 of the License, or - (at your option) any later version. - - This program is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - GNU General Public License for more details. - - You should have received a copy of the GNU General Public License - along with this program; if not, write to the Free Software - Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ -/* ------------------------------------------------------------------------- */ - -/* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi> and - Frodo Looijaard <frodol@dds.nl> ,and also from Martin Bailey - <mbailey@littlefeet-inc.com> */ - -/* Partially rewriten by Oleg I. Vdovikin <vdovikin@jscc.ru> to handle multiple - messages, proper stop/repstart signaling during receive, - added detect code */ +/* + * i2c-algo-pcf.c i2c driver algorithms for PCF8584 adapters + * + * Copyright (C) 1995-1997 Simon G. Vogl + * 1998-2000 Hans Berglund + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + * + * With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi> and + * Frodo Looijaard <frodol@dds.nl>, and also from Martin Bailey + * <mbailey@littlefeet-inc.com> + * + * Partially rewriten by Oleg I. Vdovikin <vdovikin@jscc.ru> to handle multiple + * messages, proper stop/repstart signaling during receive, added detect code + */ #include <linux/kernel.h> #include <linux/module.h> @@ -38,17 +37,18 @@ #include "i2c-algo-pcf.h" -#define DEB2(x) if (i2c_debug>=2) x |