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authorLinus Torvalds <torvalds@linux-foundation.org>2016-01-14 11:25:37 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2016-01-14 11:25:37 -0800
commit32250e4a5fa0b618044afa59fba01093a4bcb14a (patch)
tree678461393befc77b25e8d68cb637529927d3c284 /drivers/i2c/busses/i2c-piix4.c
parent5339f9d4c2ceccab00b28d65bd5c2b2cd6a3de05 (diff)
parentc698d639f72b55686ec3518d2bc8dc5f2eca9354 (diff)
Merge branch 'i2c/for-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c updates from Wolfram Sang: "Quite some driver updates: - piix4 can now handle multiplexed adapters - brcmstb, xlr, eg20t, designware drivers support more SoCs - emev2 gained i2c slave support - img-scb and rcar got bigger refactoring to remove issues - lots of common driver updates i2c core changes: - new quirk flag when an adapter does not support clock stretching, so clients can be configured to avoid that if possible - added a helper function to retrieve timing parameters from firmware (with rcar being the first user) - "multi-master" DT binding added so drivers can adapt to this setting (like disabling PM to keep arbitration working) - RuntimePM for the logical adapter device is now always enabled by the core to ensure propagation from childs to the parent (the HW device) - new macro builtin_i2c_driver to reduce boilerplate" * 'i2c/for-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (70 commits) i2c: create builtin_i2c_driver to avoid registration boilerplate i2c: imx: fix i2c resource leak with dma transfer dt-bindings: i2c: eeprom: add another EEPROM device dt-bindings: move I2C eeprom descriptions to the proper file i2c: designware: Do not require clock when SSCN and FFCN are provided DT: i2c: trivial-devices: Add Epson RX8010 and MPL3115 i2c: s3c2410: remove superfluous runtime PM calls i2c: always enable RuntimePM for the adapter device i2c: designware: retry transfer on transient failure i2c: ibm_iic: rename i2c_timings struct due to clash with generic version i2c: designware: Add support for AMD Seattle I2C i2c: imx: Remove unneeded comments i2c: st: use to_platform_device() i2c: designware: use to_pci_dev() i2c: brcmstb: Adding support for CM and DSL SoCs i2c: mediatek: fix i2c multi transfer issue in high speed mode i2c: imx: improve code readability i2c: imx: Improve message log when DMA is not used i2c: imx: add runtime pm support to improve the performance i2c: imx: init bus recovery info before adding i2c adapter ...
Diffstat (limited to 'drivers/i2c/busses/i2c-piix4.c')
-rw-r--r--drivers/i2c/busses/i2c-piix4.c202
1 files changed, 171 insertions, 31 deletions
diff --git a/drivers/i2c/busses/i2c-piix4.c b/drivers/i2c/busses/i2c-piix4.c
index 630bce68bf38..e04598595073 100644
--- a/drivers/i2c/busses/i2c-piix4.c
+++ b/drivers/i2c/busses/i2c-piix4.c
@@ -23,6 +23,9 @@
Note: we assume there can only be one device, with one or more
SMBus interfaces.
+ The device can register multiple i2c_adapters (up to PIIX4_MAX_ADAPTERS).
+ For devices supporting multiple ports the i2c_adapter should provide
+ an i2c_algorithm to access them.
*/
#include <linux/module.h>
@@ -37,6 +40,7 @@
#include <linux/dmi.h>
#include <linux/acpi.h>
#include <linux/io.h>
+#include <linux/mutex.h>
/* PIIX4 SMBus address offsets */
@@ -75,6 +79,16 @@
#define PIIX4_WORD_DATA 0x0C
#define PIIX4_BLOCK_DATA 0x14
+/* Multi-port constants */
+#define PIIX4_MAX_ADAPTERS 4
+
+/* SB800 constants */
+#define SB800_PIIX4_SMB_IDX 0xcd6
+
+/* SB800 port is selected by bits 2:1 of the smb_en register (0x2c) */
+#define SB800_PIIX4_PORT_IDX 0x2c
+#define SB800_PIIX4_PORT_IDX_MASK 0x06
+
/* insmod parameters */
/* If force is set to anything different from 0, we forcibly enable the
@@ -122,8 +136,19 @@ static const struct dmi_system_id piix4_dmi_ibm[] = {
{ },
};
+/* SB800 globals */
+static const char *piix4_main_port_names_sb800[PIIX4_MAX_ADAPTERS] = {
+ "SDA0", "SDA2", "SDA3", "SDA4"
+};
+static const char *piix4_aux_port_name_sb800 = "SDA1";
+
struct i2c_piix4_adapdata {
unsigned short smba;
+
+ /* SB800 */
+ bool sb800_main;
+ unsigned short port;
+ struct mutex *mutex;
};
static int piix4_setup(struct pci_dev *PIIX4_dev,
@@ -229,7 +254,6 @@ static int piix4_setup_sb800(struct pci_dev *PIIX4_dev,
const struct pci_device_id *id, u8 aux)
{
unsigned short piix4_smba;
- unsigned short smba_idx = 0xcd6;
u8 smba_en_lo, smba_en_hi, smb_en, smb_en_status;
u8 i2ccfg, i2ccfg_offset = 0x10;
@@ -251,16 +275,10 @@ static int piix4_setup_sb800(struct pci_dev *PIIX4_dev,
else
smb_en = (aux) ? 0x28 : 0x2c;
- if (!request_region(smba_idx, 2, "smba_idx")) {
- dev_err(&PIIX4_dev->dev, "SMBus base address index region "
- "0x%x already in use!\n", smba_idx);
- return -EBUSY;
- }
- outb_p(smb_en, smba_idx);
- smba_en_lo = inb_p(smba_idx + 1);
- outb_p(smb_en + 1, smba_idx);
- smba_en_hi = inb_p(smba_idx + 1);
- release_region(smba_idx, 2);
+ outb_p(smb_en, SB800_PIIX4_SMB_IDX);
+ smba_en_lo = inb_p(SB800_PIIX4_SMB_IDX + 1);
+ outb_p(smb_en + 1, SB800_PIIX4_SMB_IDX);
+ smba_en_hi = inb_p(SB800_PIIX4_SMB_IDX + 1);
if (!smb_en) {
smb_en_status = smba_en_lo & 0x10;
@@ -483,7 +501,7 @@ static s32 piix4_access(struct i2c_adapter * adap, u16 addr,
if (len == 0 || len > I2C_SMBUS_BLOCK_MAX)
return -EINVAL;
outb_p(len, SMBHSTDAT0);
- i = inb_p(SMBHSTCNT); /* Reset SMBBLKDAT */
+ inb_p(SMBHSTCNT); /* Reset SMBBLKDAT */
for (i = 1; i <= len; i++)
outb_p(data->block[i], SMBBLKDAT);
}
@@ -516,7 +534,7 @@ static s32 piix4_access(struct i2c_adapter * adap, u16 addr,
data->block[0] = inb_p(SMBHSTDAT0);
if (data->block[0] == 0 || data->block[0] > I2C_SMBUS_BLOCK_MAX)
return -EPROTO;
- i = inb_p(SMBHSTCNT); /* Reset SMBBLKDAT */
+ inb_p(SMBHSTCNT); /* Reset SMBBLKDAT */
for (i = 1; i <= data->block[0]; i++)
data->block[i] = inb_p(SMBBLKDAT);
break;
@@ -524,6 +542,43 @@ static s32 piix4_access(struct i2c_adapter * adap, u16 addr,
return 0;
}
+/*
+ * Handles access to multiple SMBus ports on the SB800.
+ * The port is selected by bits 2:1 of the smb_en register (0x2c).
+ * Returns negative errno on error.
+ *
+ * Note: The selected port must be returned to the initial selection to avoid
+ * problems on certain systems.
+ */
+static s32 piix4_access_sb800(struct i2c_adapter *adap, u16 addr,
+ unsigned short flags, char read_write,
+ u8 command, int size, union i2c_smbus_data *data)
+{
+ struct i2c_piix4_adapdata *adapdata = i2c_get_adapdata(adap);
+ u8 smba_en_lo;
+ u8 port;
+ int retval;
+
+ mutex_lock(adapdata->mutex);
+
+ outb_p(SB800_PIIX4_PORT_IDX, SB800_PIIX4_SMB_IDX);
+ smba_en_lo = inb_p(SB800_PIIX4_SMB_IDX + 1);
+
+ port = adapdata->port;
+ if ((smba_en_lo & SB800_PIIX4_PORT_IDX_MASK) != (port << 1))
+ outb_p((smba_en_lo & ~SB800_PIIX4_PORT_IDX_MASK) | (port << 1),
+ SB800_PIIX4_SMB_IDX + 1);
+
+ retval = piix4_access(adap, addr, flags, read_write,
+ command, size, data);
+
+ outb_p(smba_en_lo, SB800_PIIX4_SMB_IDX + 1);
+
+ mutex_unlock(adapdata->mutex);
+
+ return retval;
+}
+
static u32 piix4_func(struct i2c_adapter *adapter)
{
return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
@@ -536,6 +591,11 @@ static const struct i2c_algorithm smbus_algorithm = {
.functionality = piix4_func,
};
+static const struct i2c_algorithm piix4_smbus_algorithm_sb800 = {
+ .smbus_xfer = piix4_access_sb800,
+ .functionality = piix4_func,
+};
+
static const struct pci_device_id piix4_ids[] = {
{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82371AB_3) },
{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82443MX_3) },
@@ -561,11 +621,11 @@ static const struct pci_device_id piix4_ids[] = {
MODULE_DEVICE_TABLE (pci, piix4_ids);
-static struct i2c_adapter *piix4_main_adapter;
+static struct i2c_adapter *piix4_main_adapters[PIIX4_MAX_ADAPTERS];
static struct i2c_adapter *piix4_aux_adapter;
static int piix4_add_adapter(struct pci_dev *dev, unsigned short smba,
- struct i2c_adapter **padap)
+ const char *name, struct i2c_adapter **padap)
{
struct i2c_adapter *adap;
struct i2c_piix4_adapdata *adapdata;
@@ -594,7 +654,7 @@ static int piix4_add_adapter(struct pci_dev *dev, unsigned short smba,
adap->dev.parent = &dev->dev;
snprintf(adap->name, sizeof(adap->name),
- "SMBus PIIX4 adapter at %04x", smba);
+ "SMBus PIIX4 adapter %s at %04x", name, smba);
i2c_set_adapdata(adap, adapdata);
@@ -611,6 +671,54 @@ static int piix4_add_adapter(struct pci_dev *dev, unsigned short smba,
return 0;
}
+static int piix4_add_adapters_sb800(struct pci_dev *dev, unsigned short smba)
+{
+ struct mutex *mutex;
+ struct i2c_piix4_adapdata *adapdata;
+ int port;
+ int retval;
+
+ mutex = kzalloc(sizeof(*mutex), GFP_KERNEL);
+ if (mutex == NULL)
+ return -ENOMEM;
+
+ mutex_init(mutex);
+
+ for (port = 0; port < PIIX4_MAX_ADAPTERS; port++) {
+ retval = piix4_add_adapter(dev, smba,
+ piix4_main_port_names_sb800[port],
+ &piix4_main_adapters[port]);
+ if (retval < 0)
+ goto error;
+
+ piix4_main_adapters[port]->algo = &piix4_smbus_algorithm_sb800;
+
+ adapdata = i2c_get_adapdata(piix4_main_adapters[port]);
+ adapdata->sb800_main = true;
+ adapdata->port = port;
+ adapdata->mutex = mutex;
+ }
+
+ return retval;
+
+error:
+ dev_err(&dev->dev,
+ "Error setting up SB800 adapters. Unregistering!\n");
+ while (--port >= 0) {
+ adapdata = i2c_get_adapdata(piix4_main_adapters[port]);
+ if (adapdata->smba) {
+ i2c_del_adapter(piix4_main_adapters[port]);
+ kfree(adapdata);
+ kfree(piix4_main_adapters[port]);
+ piix4_main_adapters[port] = NULL;
+ }
+ }
+
+ kfree(mutex);
+
+ return retval;
+}
+
static int piix4_probe(struct pci_dev *dev, const struct pci_device_id *id)
{
int retval;
@@ -618,20 +726,41 @@ static int piix4_probe(struct pci_dev *dev, const struct pci_device_id *id)
if ((dev->vendor == PCI_VENDOR_ID_ATI &&
dev->device == PCI_DEVICE_ID_ATI_SBX00_SMBUS &&
dev->revision >= 0x40) ||
- dev->vendor == PCI_VENDOR_ID_AMD)
+ dev->vendor == PCI_VENDOR_ID_AMD) {
+ if (!request_region(SB800_PIIX4_SMB_IDX, 2, "smba_idx")) {
+ dev_err(&dev->dev,
+ "SMBus base address index region 0x%x already in use!\n",
+ SB800_PIIX4_SMB_IDX);
+ return -EBUSY;
+ }
+
/* base address location etc changed in SB800 */
retval = piix4_setup_sb800(dev, id, 0);
- else
- retval = piix4_setup(dev, id);
+ if (retval < 0) {
+ release_region(SB800_PIIX4_SMB_IDX, 2);
+ return retval;
+ }
- /* If no main SMBus found, give up */
- if (retval < 0)
- return retval;
+ /*
+ * Try to register multiplexed main SMBus adapter,
+ * give up if we can't
+ */
+ retval = piix4_add_adapters_sb800(dev, retval);
+ if (retval < 0) {
+ release_region(SB800_PIIX4_SMB_IDX, 2);
+ return retval;
+ }
+ } else {
+ retval = piix4_setup(dev, id);
+ if (retval < 0)
+ return retval;
- /* Try to register main SMBus adapter, give up if we can't */
- retval = piix4_add_adapter(dev, retval, &piix4_main_adapter);
- if (retval < 0)
- return retval;
+ /* Try to register main SMBus adapter, give up if we can't */
+ retval = piix4_add_adapter(dev, retval, "main",
+ &piix4_main_adapters[0]);
+ if (retval < 0)
+ return retval;
+ }
/* Check for auxiliary SMBus on some AMD chipsets */
retval = -ENODEV;
@@ -654,7 +783,8 @@ static int piix4_probe(struct pci_dev *dev, const struct pci_device_id *id)
if (retval > 0) {
/* Try to add the aux adapter if it exists,
* piix4_add_adapter will clean up if this fails */
- piix4_add_adapter(dev, retval, &piix4_aux_adapter);
+ piix4_add_adapter(dev, retval, piix4_aux_port_name_sb800,
+ &piix4_aux_adapter);
}
return 0;
@@ -666,7 +796,13 @@ static void piix4_adap_remove(struct i2c_adapter *adap)
if (adapdata->smba) {
i2c_del_adapter(adap);
- release_region(adapdata->smba, SMBIOSIZE);
+ if (adapdata->port == 0) {
+ release_region(adapdata->smba, SMBIOSIZE);
+ if (adapdata->sb800_main) {
+ kfree(adapdata->mutex);
+ release_region(SB800_PIIX4_SMB_IDX, 2);
+ }
+ }
kfree(adapdata);
kfree(adap);
}
@@ -674,9 +810,13 @@ static void piix4_adap_remove(struct i2c_adapter *adap)
static void piix4_remove(struct pci_dev *dev)
{
- if (piix4_main_adapter) {
- piix4_adap_remove(piix4_main_adapter);
- piix4_main_adapter = NULL;
+ int port = PIIX4_MAX_ADAPTERS;
+
+ while (--port >= 0) {
+ if (piix4_main_adapters[port]) {
+ piix4_adap_remove(piix4_main_adapters[port]);
+ piix4_main_adapters[port] = NULL;
+ }
}
if (piix4_aux_adapter) {