Commit 8f5d2708 authored by Linus Torvalds's avatar Linus Torvalds

Merge branch 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux

Pull i2c new drivers from Wolfram Sang:
 "Here is a pull request from i2c hoping for the "new driver" rule.

  Originally, I wanted to send this request during the merge window, but
  code checkers with very recent additions complained, so a few fixups
  were needed.  So, some more time went by and I merged rc1 to get a
  stable base"

So the "new driver" rule is really about drivers that people absolutely
need for the kernel to work on new hardware, which is not so much the
case for i2c.  So I considered not pulling this, but eventually
relented.

Just for FYI: the whole (and only) point of "new drivers" is not that
new drivers cannot regress things (they can, and they have - by
triggering badly tested code on machines that never triggered that code
before), but because they can bring to life machines that otherwise
wouldn't be useful at all without the drivers.

So the new driver rule is for essential things that actual consumers
would care about, ie devices like networking or disk drivers that matter
to normal people (not server people - they run old kernels anyway, so
mainlining new drivers is irrelevant for them).

* 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: sun6-p2wi: fix call to snprintf
  i2c: rk3x: add NULL entry to the end of_device_id array
  i2c: sun6i-p2wi: use proper return value in probe
  i2c: sunxi: add P2WI (Push/Pull 2 Wire Interface) controller support
  i2c: sunxi: add P2WI DT bindings documentation
  i2c: rk3x: add driver for Rockchip RK3xxx SoC I2C adapter
parents 2dfded82 f0b1f644
* Rockchip RK3xxx I2C controller
This driver interfaces with the native I2C controller present in Rockchip
RK3xxx SoCs.
Required properties :
- reg : Offset and length of the register set for the device
- compatible : should be "rockchip,rk3066-i2c", "rockchip,rk3188-i2c" or
"rockchip,rk3288-i2c".
- interrupts : interrupt number
- clocks : parent clock
Required on RK3066, RK3188 :
- rockchip,grf : the phandle of the syscon node for the general register
file (GRF)
- on those SoCs an alias with the correct I2C bus ID (bit offset in the GRF)
is also required.
Optional properties :
- clock-frequency : SCL frequency to use (in Hz). If omitted, 100kHz is used.
Example:
aliases {
i2c0 = &i2c0;
}
i2c0: i2c@2002d000 {
compatible = "rockchip,rk3188-i2c";
reg = <0x2002d000 0x1000>;
interrupts = <GIC_SPI 40 IRQ_TYPE_LEVEL_HIGH>;
#address-cells = <1>;
#size-cells = <0>;
rockchip,grf = <&grf>;
clock-names = "i2c";
clocks = <&cru PCLK_I2C0>;
};
* Allwinner P2WI (Push/Pull 2 Wire Interface) controller
Required properties :
- reg : Offset and length of the register set for the device.
- compatible : Should one of the following:
- "allwinner,sun6i-a31-p2wi"
- interrupts : The interrupt line connected to the P2WI peripheral.
- clocks : The gate clk connected to the P2WI peripheral.
- resets : The reset line connected to the P2WI peripheral.
Optional properties :
- clock-frequency : Desired P2WI bus clock frequency in Hz. If not set the
default frequency is 100kHz
A P2WI may contain one child node encoding a P2WI slave device.
Slave device properties:
Required properties:
- reg : the I2C slave address used during the initialization
process to switch from I2C to P2WI mode
Example:
p2wi@01f03400 {
compatible = "allwinner,sun6i-a31-p2wi";
reg = <0x01f03400 0x400>;
interrupts = <0 39 4>;
clocks = <&apb0_gates 3>;
clock-frequency = <6000000>;
resets = <&apb0_rst 3>;
axp221: pmic@68 {
compatible = "x-powers,axp221";
reg = <0x68>;
/* ... */
};
};
...@@ -676,6 +676,16 @@ config I2C_RIIC ...@@ -676,6 +676,16 @@ config I2C_RIIC
This driver can also be built as a module. If so, the module This driver can also be built as a module. If so, the module
will be called i2c-riic. will be called i2c-riic.
config I2C_RK3X
tristate "Rockchip RK3xxx I2C adapter"
depends on OF
help
Say Y here to include support for the I2C adapter in Rockchip RK3xxx
SoCs.
This driver can also be built as a module. If so, the module will
be called i2c-rk3x.
config HAVE_S3C2410_I2C config HAVE_S3C2410_I2C
bool bool
help help
...@@ -764,6 +774,19 @@ config I2C_STU300 ...@@ -764,6 +774,19 @@ config I2C_STU300
This driver can also be built as a module. If so, the module This driver can also be built as a module. If so, the module
will be called i2c-stu300. will be called i2c-stu300.
config I2C_SUN6I_P2WI
tristate "Allwinner sun6i internal P2WI controller"
depends on RESET_CONTROLLER
depends on MACH_SUN6I || COMPILE_TEST
help
If you say yes to this option, support will be included for the
P2WI (Push/Pull 2 Wire Interface) controller embedded in some sunxi
SOCs.
The P2WI looks like an SMBus controller (which supports only byte
accesses), except that it only supports one slave device.
This interface is used to connect to specific PMIC devices (like the
AXP221).
config I2C_TEGRA config I2C_TEGRA
tristate "NVIDIA Tegra internal I2C controller" tristate "NVIDIA Tegra internal I2C controller"
depends on ARCH_TEGRA depends on ARCH_TEGRA
......
...@@ -66,6 +66,7 @@ obj-$(CONFIG_I2C_PXA) += i2c-pxa.o ...@@ -66,6 +66,7 @@ obj-$(CONFIG_I2C_PXA) += i2c-pxa.o
obj-$(CONFIG_I2C_PXA_PCI) += i2c-pxa-pci.o obj-$(CONFIG_I2C_PXA_PCI) += i2c-pxa-pci.o
obj-$(CONFIG_I2C_QUP) += i2c-qup.o obj-$(CONFIG_I2C_QUP) += i2c-qup.o
obj-$(CONFIG_I2C_RIIC) += i2c-riic.o obj-$(CONFIG_I2C_RIIC) += i2c-riic.o
obj-$(CONFIG_I2C_RK3X) += i2c-rk3x.o
obj-$(CONFIG_I2C_S3C2410) += i2c-s3c2410.o obj-$(CONFIG_I2C_S3C2410) += i2c-s3c2410.o
obj-$(CONFIG_I2C_S6000) += i2c-s6000.o obj-$(CONFIG_I2C_S6000) += i2c-s6000.o
obj-$(CONFIG_I2C_SH7760) += i2c-sh7760.o obj-$(CONFIG_I2C_SH7760) += i2c-sh7760.o
...@@ -74,6 +75,7 @@ obj-$(CONFIG_I2C_SIMTEC) += i2c-simtec.o ...@@ -74,6 +75,7 @@ obj-$(CONFIG_I2C_SIMTEC) += i2c-simtec.o
obj-$(CONFIG_I2C_SIRF) += i2c-sirf.o obj-$(CONFIG_I2C_SIRF) += i2c-sirf.o
obj-$(CONFIG_I2C_ST) += i2c-st.o obj-$(CONFIG_I2C_ST) += i2c-st.o
obj-$(CONFIG_I2C_STU300) += i2c-stu300.o obj-$(CONFIG_I2C_STU300) += i2c-stu300.o
obj-$(CONFIG_I2C_SUN6I_P2WI) += i2c-sun6i-p2wi.o
obj-$(CONFIG_I2C_TEGRA) += i2c-tegra.o obj-$(CONFIG_I2C_TEGRA) += i2c-tegra.o
obj-$(CONFIG_I2C_VERSATILE) += i2c-versatile.o obj-$(CONFIG_I2C_VERSATILE) += i2c-versatile.o
obj-$(CONFIG_I2C_WMT) += i2c-wmt.o obj-$(CONFIG_I2C_WMT) += i2c-wmt.o
......
This diff is collapsed.
/*
* P2WI (Push-Pull Two Wire Interface) bus driver.
*
* Author: Boris BREZILLON <boris.brezillon@free-electrons.com>
*
* This file is licensed under the terms of the GNU General Public License
* version 2. This program is licensed "as is" without any warranty of any
* kind, whether express or implied.
*
* The P2WI controller looks like an SMBus controller which only supports byte
* data transfers. But, it differs from standard SMBus protocol on several
* aspects:
* - it supports only one slave device, and thus drop the address field
* - it adds a parity bit every 8bits of data
* - only one read access is required to read a byte (instead of a write
* followed by a read access in standard SMBus protocol)
* - there's no Ack bit after each byte transfer
*
* This means this bus cannot be used to interface with standard SMBus
* devices (the only known device to support this interface is the AXP221
* PMIC).
*
*/
#include <linux/clk.h>
#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/io.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/reset.h>
/* P2WI registers */
#define P2WI_CTRL 0x0
#define P2WI_CCR 0x4
#define P2WI_INTE 0x8
#define P2WI_INTS 0xc
#define P2WI_DADDR0 0x10
#define P2WI_DADDR1 0x14
#define P2WI_DLEN 0x18
#define P2WI_DATA0 0x1c
#define P2WI_DATA1 0x20
#define P2WI_LCR 0x24
#define P2WI_PMCR 0x28
/* CTRL fields */
#define P2WI_CTRL_START_TRANS BIT(7)
#define P2WI_CTRL_ABORT_TRANS BIT(6)
#define P2WI_CTRL_GLOBAL_INT_ENB BIT(1)
#define P2WI_CTRL_SOFT_RST BIT(0)
/* CLK CTRL fields */
#define P2WI_CCR_SDA_OUT_DELAY(v) (((v) & 0x7) << 8)
#define P2WI_CCR_MAX_CLK_DIV 0xff
#define P2WI_CCR_CLK_DIV(v) ((v) & P2WI_CCR_MAX_CLK_DIV)
/* STATUS fields */
#define P2WI_INTS_TRANS_ERR_ID(v) (((v) >> 8) & 0xff)
#define P2WI_INTS_LOAD_BSY BIT(2)
#define P2WI_INTS_TRANS_ERR BIT(1)
#define P2WI_INTS_TRANS_OVER BIT(0)
/* DATA LENGTH fields*/
#define P2WI_DLEN_READ BIT(4)
#define P2WI_DLEN_DATA_LENGTH(v) ((v - 1) & 0x7)
/* LINE CTRL fields*/
#define P2WI_LCR_SCL_STATE BIT(5)
#define P2WI_LCR_SDA_STATE BIT(4)
#define P2WI_LCR_SCL_CTL BIT(3)
#define P2WI_LCR_SCL_CTL_EN BIT(2)
#define P2WI_LCR_SDA_CTL BIT(1)
#define P2WI_LCR_SDA_CTL_EN BIT(0)
/* PMU MODE CTRL fields */
#define P2WI_PMCR_PMU_INIT_SEND BIT(31)
#define P2WI_PMCR_PMU_INIT_DATA(v) (((v) & 0xff) << 16)
#define P2WI_PMCR_PMU_MODE_REG(v) (((v) & 0xff) << 8)
#define P2WI_PMCR_PMU_DEV_ADDR(v) ((v) & 0xff)
#define P2WI_MAX_FREQ 6000000
struct p2wi {
struct i2c_adapter adapter;
struct completion complete;
unsigned int status;
void __iomem *regs;
struct clk *clk;
struct reset_control *rstc;
int slave_addr;
};
static irqreturn_t p2wi_interrupt(int irq, void *dev_id)
{
struct p2wi *p2wi = dev_id;
unsigned long status;
status = readl(p2wi->regs + P2WI_INTS);
p2wi->status = status;
/* Clear interrupts */
status &= (P2WI_INTS_LOAD_BSY | P2WI_INTS_TRANS_ERR |
P2WI_INTS_TRANS_OVER);
writel(status, p2wi->regs + P2WI_INTS);
complete(&p2wi->complete);
return IRQ_HANDLED;
}
static u32 p2wi_functionality(struct i2c_adapter *adap)
{
return I2C_FUNC_SMBUS_BYTE_DATA;
}
static int p2wi_smbus_xfer(struct i2c_adapter *adap, u16 addr,
unsigned short flags, char read_write,
u8 command, int size, union i2c_smbus_data *data)
{
struct p2wi *p2wi = i2c_get_adapdata(adap);
unsigned long dlen = P2WI_DLEN_DATA_LENGTH(1);
if (p2wi->slave_addr >= 0 && addr != p2wi->slave_addr) {
dev_err(&adap->dev, "invalid P2WI address\n");
return -EINVAL;
}
if (!data)
return -EINVAL;
writel(command, p2wi->regs + P2WI_DADDR0);
if (read_write == I2C_SMBUS_READ)
dlen |= P2WI_DLEN_READ;
else
writel(data->byte, p2wi->regs + P2WI_DATA0);
writel(dlen, p2wi->regs + P2WI_DLEN);
if (readl(p2wi->regs + P2WI_CTRL) & P2WI_CTRL_START_TRANS) {
dev_err(&adap->dev, "P2WI bus busy\n");
return -EBUSY;
}
reinit_completion(&p2wi->complete);
writel(P2WI_INTS_LOAD_BSY | P2WI_INTS_TRANS_ERR | P2WI_INTS_TRANS_OVER,
p2wi->regs + P2WI_INTE);
writel(P2WI_CTRL_START_TRANS | P2WI_CTRL_GLOBAL_INT_ENB,
p2wi->regs + P2WI_CTRL);
wait_for_completion(&p2wi->complete);
if (p2wi->status & P2WI_INTS_LOAD_BSY) {
dev_err(&adap->dev, "P2WI bus busy\n");
return -EBUSY;
}
if (p2wi->status & P2WI_INTS_TRANS_ERR) {
dev_err(&adap->dev, "P2WI bus xfer error\n");
return -ENXIO;
}
if (read_write == I2C_SMBUS_READ)
data->byte = readl(p2wi->regs + P2WI_DATA0);
return 0;
}
static const struct i2c_algorithm p2wi_algo = {
.smbus_xfer = p2wi_smbus_xfer,
.functionality = p2wi_functionality,
};
static const struct of_device_id p2wi_of_match_table[] = {
{ .compatible = "allwinner,sun6i-a31-p2wi" },
{}
};
MODULE_DEVICE_TABLE(of, p2wi_of_match_table);
static int p2wi_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct device_node *np = dev->of_node;
struct device_node *childnp;
unsigned long parent_clk_freq;
u32 clk_freq = 100000;
struct resource *r;
struct p2wi *p2wi;
u32 slave_addr;
int clk_div;
int irq;
int ret;
of_property_read_u32(np, "clock-frequency", &clk_freq);
if (clk_freq > P2WI_MAX_FREQ) {
dev_err(dev,
"required clock-frequency (%u Hz) is too high (max = 6MHz)",
clk_freq);
return -EINVAL;
}
if (of_get_child_count(np) > 1) {
dev_err(dev, "P2WI only supports one slave device\n");
return -EINVAL;
}
p2wi = devm_kzalloc(dev, sizeof(struct p2wi), GFP_KERNEL);
if (!p2wi)
return -ENOMEM;
p2wi->slave_addr = -1;
/*
* Authorize a p2wi node without any children to be able to use an
* i2c-dev from userpace.
* In this case the slave_addr is set to -1 and won't be checked when
* launching a P2WI transfer.
*/
childnp = of_get_next_available_child(np, NULL);
if (childnp) {
ret = of_property_read_u32(childnp, "reg", &slave_addr);
if (ret) {
dev_err(dev, "invalid slave address on node %s\n",
childnp->full_name);
return -EINVAL;
}
p2wi->slave_addr = slave_addr;
}
r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
p2wi->regs = devm_ioremap_resource(dev, r);
if (IS_ERR(p2wi->regs))
return PTR_ERR(p2wi->regs);
strlcpy(p2wi->adapter.name, pdev->name, sizeof(p2wi->adapter.name));
irq = platform_get_irq(pdev, 0);
if (irq < 0) {
dev_err(dev, "failed to retrieve irq: %d\n", irq);
return irq;
}
p2wi->clk = devm_clk_get(dev, NULL);
if (IS_ERR(p2wi->clk)) {
ret = PTR_ERR(p2wi->clk);
dev_err(dev, "failed to retrieve clk: %d\n", ret);
return ret;
}
ret = clk_prepare_enable(p2wi->clk);
if (ret) {
dev_err(dev, "failed to enable clk: %d\n", ret);
return ret;
}
parent_clk_freq = clk_get_rate(p2wi->clk);
p2wi->rstc = devm_reset_control_get(dev, NULL);
if (IS_ERR(p2wi->rstc)) {
ret = PTR_ERR(p2wi->rstc);
dev_err(dev, "failed to retrieve reset controller: %d\n", ret);
goto err_clk_disable;
}
ret = reset_control_deassert(p2wi->rstc);
if (ret) {
dev_err(dev, "failed to deassert reset line: %d\n", ret);
goto err_clk_disable;
}
init_completion(&p2wi->complete);
p2wi->adapter.dev.parent = dev;
p2wi->adapter.algo = &p2wi_algo;
p2wi->adapter.owner = THIS_MODULE;
p2wi->adapter.dev.of_node = pdev->dev.of_node;
platform_set_drvdata(pdev, p2wi);
i2c_set_adapdata(&p2wi->adapter, p2wi);
ret = devm_request_irq(dev, irq, p2wi_interrupt, 0, pdev->name, p2wi);
if (ret) {
dev_err(dev, "can't register interrupt handler irq%d: %d\n",
irq, ret);
goto err_reset_assert;
}
writel(P2WI_CTRL_SOFT_RST, p2wi->regs + P2WI_CTRL);
clk_div = parent_clk_freq / clk_freq;
if (!clk_div) {
dev_warn(dev,
"clock-frequency is too high, setting it to %lu Hz\n",
parent_clk_freq);
clk_div = 1;
} else if (clk_div > P2WI_CCR_MAX_CLK_DIV) {
dev_warn(dev,
"clock-frequency is too low, setting it to %lu Hz\n",
parent_clk_freq / P2WI_CCR_MAX_CLK_DIV);
clk_div = P2WI_CCR_MAX_CLK_DIV;
}
writel(P2WI_CCR_SDA_OUT_DELAY(1) | P2WI_CCR_CLK_DIV(clk_div),
p2wi->regs + P2WI_CCR);
ret = i2c_add_adapter(&p2wi->adapter);
if (!ret)
return 0;
err_reset_assert:
reset_control_assert(p2wi->rstc);
err_clk_disable:
clk_disable_unprepare(p2wi->clk);
return ret;
}
static int p2wi_remove(struct platform_device *dev)
{
struct p2wi *p2wi = platform_get_drvdata(dev);
reset_control_assert(p2wi->rstc);
clk_disable_unprepare(p2wi->clk);
i2c_del_adapter(&p2wi->adapter);
return 0;
}
static struct platform_driver p2wi_driver = {
.probe = p2wi_probe,
.remove = p2wi_remove,
.driver = {
.owner = THIS_MODULE,
.name = "i2c-sunxi-p2wi",
.of_match_table = p2wi_of_match_table,
},
};
module_platform_driver(p2wi_driver);
MODULE_AUTHOR("Boris BREZILLON <boris.brezillon@free-electrons.com>");
MODULE_DESCRIPTION("Allwinner P2WI driver");
MODULE_LICENSE("GPL v2");
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment