linux/drivers/i2c/busses/i2c-designware-pcidrv.c
Dustin Byford 8eb5c87a92 i2c: add ACPI support for I2C mux ports
Although I2C mux devices are easily enumerated using ACPI (_HID/_CID or
device property compatible string match), enumerating I2C client devices
connected through an I2C mux needs a little extra work.

This change implements a method for describing an I2C device hierarchy that
includes mux devices by using an ACPI Device() for each mux channel along
with an _ADR to set the channel number for the device.  See
Documentation/acpi/i2c-muxes.txt for a simple example.

To make this work the ismt, i801, and designware pci/platform devs now
share an ACPI companion with their I2C adapter dev similar to how it's done
in OF.  This is done on the assumption that power management functions will
not be called directly on the I2C dev that is sharing the ACPI node.

Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Dustin Byford <dustin@cumulusnetworks.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-10-25 15:49:46 +01:00

323 lines
8.0 KiB
C

/*
* Synopsys DesignWare I2C adapter driver (master only).
*
* Based on the TI DAVINCI I2C adapter driver.
*
* Copyright (C) 2006 Texas Instruments.
* Copyright (C) 2007 MontaVista Software Inc.
* Copyright (C) 2009 Provigent Ltd.
* Copyright (C) 2011, 2015 Intel Corporation.
*
* ----------------------------------------------------------------------------
*
* 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.
* ----------------------------------------------------------------------------
*
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/i2c.h>
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/err.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/pci.h>
#include <linux/pm_runtime.h>
#include <linux/acpi.h>
#include "i2c-designware-core.h"
#define DRIVER_NAME "i2c-designware-pci"
enum dw_pci_ctl_id_t {
medfield_0,
medfield_1,
medfield_2,
medfield_3,
medfield_4,
medfield_5,
baytrail,
haswell,
};
struct dw_scl_sda_cfg {
u32 ss_hcnt;
u32 fs_hcnt;
u32 ss_lcnt;
u32 fs_lcnt;
u32 sda_hold;
};
struct dw_pci_controller {
u32 bus_num;
u32 bus_cfg;
u32 tx_fifo_depth;
u32 rx_fifo_depth;
u32 clk_khz;
u32 functionality;
struct dw_scl_sda_cfg *scl_sda_cfg;
};
#define INTEL_MID_STD_CFG (DW_IC_CON_MASTER | \
DW_IC_CON_SLAVE_DISABLE | \
DW_IC_CON_RESTART_EN)
#define DW_DEFAULT_FUNCTIONALITY (I2C_FUNC_I2C | \
I2C_FUNC_SMBUS_BYTE | \
I2C_FUNC_SMBUS_BYTE_DATA | \
I2C_FUNC_SMBUS_WORD_DATA | \
I2C_FUNC_SMBUS_I2C_BLOCK)
/* BayTrail HCNT/LCNT/SDA hold time */
static struct dw_scl_sda_cfg byt_config = {
.ss_hcnt = 0x200,
.fs_hcnt = 0x55,
.ss_lcnt = 0x200,
.fs_lcnt = 0x99,
.sda_hold = 0x6,
};
/* Haswell HCNT/LCNT/SDA hold time */
static struct dw_scl_sda_cfg hsw_config = {
.ss_hcnt = 0x01b0,
.fs_hcnt = 0x48,
.ss_lcnt = 0x01fb,
.fs_lcnt = 0xa0,
.sda_hold = 0x9,
};
static struct dw_pci_controller dw_pci_controllers[] = {
[medfield_0] = {
.bus_num = 0,
.bus_cfg = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
.tx_fifo_depth = 32,
.rx_fifo_depth = 32,
.clk_khz = 25000,
},
[medfield_1] = {
.bus_num = 1,
.bus_cfg = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
.tx_fifo_depth = 32,
.rx_fifo_depth = 32,
.clk_khz = 25000,
},
[medfield_2] = {
.bus_num = 2,
.bus_cfg = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
.tx_fifo_depth = 32,
.rx_fifo_depth = 32,
.clk_khz = 25000,
},
[medfield_3] = {
.bus_num = 3,
.bus_cfg = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_STD,
.tx_fifo_depth = 32,
.rx_fifo_depth = 32,
.clk_khz = 25000,
},
[medfield_4] = {
.bus_num = 4,
.bus_cfg = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
.tx_fifo_depth = 32,
.rx_fifo_depth = 32,
.clk_khz = 25000,
},
[medfield_5] = {
.bus_num = 5,
.bus_cfg = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
.tx_fifo_depth = 32,
.rx_fifo_depth = 32,
.clk_khz = 25000,
},
[baytrail] = {
.bus_num = -1,
.bus_cfg = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
.tx_fifo_depth = 32,
.rx_fifo_depth = 32,
.functionality = I2C_FUNC_10BIT_ADDR,
.scl_sda_cfg = &byt_config,
},
[haswell] = {
.bus_num = -1,
.bus_cfg = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
.tx_fifo_depth = 32,
.rx_fifo_depth = 32,
.functionality = I2C_FUNC_10BIT_ADDR,
.scl_sda_cfg = &hsw_config,
},
};
#ifdef CONFIG_PM
static int i2c_dw_pci_suspend(struct device *dev)
{
struct pci_dev *pdev = container_of(dev, struct pci_dev, dev);
i2c_dw_disable(pci_get_drvdata(pdev));
return 0;
}
static int i2c_dw_pci_resume(struct device *dev)
{
struct pci_dev *pdev = container_of(dev, struct pci_dev, dev);
return i2c_dw_init(pci_get_drvdata(pdev));
}
#endif
static UNIVERSAL_DEV_PM_OPS(i2c_dw_pm_ops, i2c_dw_pci_suspend,
i2c_dw_pci_resume, NULL);
static u32 i2c_dw_get_clk_rate_khz(struct dw_i2c_dev *dev)
{
return dev->controller->clk_khz;
}
static int i2c_dw_pci_probe(struct pci_dev *pdev,
const struct pci_device_id *id)
{
struct dw_i2c_dev *dev;
struct i2c_adapter *adap;
int r;
struct dw_pci_controller *controller;
struct dw_scl_sda_cfg *cfg;
if (id->driver_data >= ARRAY_SIZE(dw_pci_controllers)) {
dev_err(&pdev->dev, "%s: invalid driver data %ld\n", __func__,
id->driver_data);
return -EINVAL;
}
controller = &dw_pci_controllers[id->driver_data];
r = pcim_enable_device(pdev);
if (r) {
dev_err(&pdev->dev, "Failed to enable I2C PCI device (%d)\n",
r);
return r;
}
r = pcim_iomap_regions(pdev, 1 << 0, pci_name(pdev));
if (r) {
dev_err(&pdev->dev, "I/O memory remapping failed\n");
return r;
}
dev = devm_kzalloc(&pdev->dev, sizeof(struct dw_i2c_dev), GFP_KERNEL);
if (!dev)
return -ENOMEM;
dev->clk = NULL;
dev->controller = controller;
dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz;
dev->base = pcim_iomap_table(pdev)[0];
dev->dev = &pdev->dev;
dev->irq = pdev->irq;
dev->functionality = controller->functionality |
DW_DEFAULT_FUNCTIONALITY;
dev->master_cfg = controller->bus_cfg;
if (controller->scl_sda_cfg) {
cfg = controller->scl_sda_cfg;
dev->ss_hcnt = cfg->ss_hcnt;
dev->fs_hcnt = cfg->fs_hcnt;
dev->ss_lcnt = cfg->ss_lcnt;
dev->fs_lcnt = cfg->fs_lcnt;
dev->sda_hold_time = cfg->sda_hold;
}
pci_set_drvdata(pdev, dev);
dev->tx_fifo_depth = controller->tx_fifo_depth;
dev->rx_fifo_depth = controller->rx_fifo_depth;
adap = &dev->adapter;
adap->owner = THIS_MODULE;
adap->class = 0;
ACPI_COMPANION_SET(&adap->dev, ACPI_COMPANION(&pdev->dev));
adap->nr = controller->bus_num;
r = i2c_dw_probe(dev);
if (r)
return r;
pm_runtime_set_autosuspend_delay(&pdev->dev, 1000);
pm_runtime_use_autosuspend(&pdev->dev);
pm_runtime_put_autosuspend(&pdev->dev);
pm_runtime_allow(&pdev->dev);
return 0;
}
static void i2c_dw_pci_remove(struct pci_dev *pdev)
{
struct dw_i2c_dev *dev = pci_get_drvdata(pdev);
i2c_dw_disable(dev);
pm_runtime_forbid(&pdev->dev);
pm_runtime_get_noresume(&pdev->dev);
i2c_del_adapter(&dev->adapter);
}
/* work with hotplug and coldplug */
MODULE_ALIAS("i2c_designware-pci");
static const struct pci_device_id i2_designware_pci_ids[] = {
/* Medfield */
{ PCI_VDEVICE(INTEL, 0x0817), medfield_3 },
{ PCI_VDEVICE(INTEL, 0x0818), medfield_4 },
{ PCI_VDEVICE(INTEL, 0x0819), medfield_5 },
{ PCI_VDEVICE(INTEL, 0x082C), medfield_0 },
{ PCI_VDEVICE(INTEL, 0x082D), medfield_1 },
{ PCI_VDEVICE(INTEL, 0x082E), medfield_2 },
/* Baytrail */
{ PCI_VDEVICE(INTEL, 0x0F41), baytrail },
{ PCI_VDEVICE(INTEL, 0x0F42), baytrail },
{ PCI_VDEVICE(INTEL, 0x0F43), baytrail },
{ PCI_VDEVICE(INTEL, 0x0F44), baytrail },
{ PCI_VDEVICE(INTEL, 0x0F45), baytrail },
{ PCI_VDEVICE(INTEL, 0x0F46), baytrail },
{ PCI_VDEVICE(INTEL, 0x0F47), baytrail },
/* Haswell */
{ PCI_VDEVICE(INTEL, 0x9c61), haswell },
{ PCI_VDEVICE(INTEL, 0x9c62), haswell },
/* Braswell / Cherrytrail */
{ PCI_VDEVICE(INTEL, 0x22C1), baytrail },
{ PCI_VDEVICE(INTEL, 0x22C2), baytrail },
{ PCI_VDEVICE(INTEL, 0x22C3), baytrail },
{ PCI_VDEVICE(INTEL, 0x22C4), baytrail },
{ PCI_VDEVICE(INTEL, 0x22C5), baytrail },
{ PCI_VDEVICE(INTEL, 0x22C6), baytrail },
{ PCI_VDEVICE(INTEL, 0x22C7), baytrail },
{ 0,}
};
MODULE_DEVICE_TABLE(pci, i2_designware_pci_ids);
static struct pci_driver dw_i2c_driver = {
.name = DRIVER_NAME,
.id_table = i2_designware_pci_ids,
.probe = i2c_dw_pci_probe,
.remove = i2c_dw_pci_remove,
.driver = {
.pm = &i2c_dw_pm_ops,
},
};
module_pci_driver(dw_i2c_driver);
MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>");
MODULE_DESCRIPTION("Synopsys DesignWare PCI I2C bus adapter");
MODULE_LICENSE("GPL");