Hi Jayachandran, On 3/3/2015 10:55 PM, Jayachandran C wrote: > From: Subhendu Sekhar Behera <sbehera@xxxxxxxxxxxx> > > Add an I2C bus driver i2c-xlp9xx.c to support the I2C block in the > XLP9xx/XLP5xx MIPS SoC. Update Kconfig and Makefile to add the > CONFIG_I2C_XLP9XX option. > > Also add document Documentation/devicetree/bindings/i2c/i2c-xlp9xx.txt > for DT compatible string "netlogic,xlp9xx-i2c". > > Signed-off-by: Subhendu Sekhar Behera <sbehera@xxxxxxxxxxxx> > Signed-off-by: Jayachandran C <jchandra@xxxxxxxxxxxx> > --- > .../devicetree/bindings/i2c/i2c-xlp9xx.txt | 22 + > drivers/i2c/busses/Kconfig | 10 + > drivers/i2c/busses/Makefile | 1 + > drivers/i2c/busses/i2c-xlp9xx.c | 446 +++++++++++++++++++++ > 4 files changed, 479 insertions(+) > create mode 100644 Documentation/devicetree/bindings/i2c/i2c-xlp9xx.txt > create mode 100644 drivers/i2c/busses/i2c-xlp9xx.c > > diff --git a/Documentation/devicetree/bindings/i2c/i2c-xlp9xx.txt b/Documentation/devicetree/bindings/i2c/i2c-xlp9xx.txt > new file mode 100644 > index 00000000..f23ae87 > --- /dev/null > +++ b/Documentation/devicetree/bindings/i2c/i2c-xlp9xx.txt > @@ -0,0 +1,22 @@ > +Device tree configuration for the I2C controller on the XLP9xx/5xx SoC > + > +Required properties: > +- compatible : should be "netlogic,xlp9xx-i2c" > +- reg : bus address start and address range size of device > +- interrupts : interrupt number > + > +Optional properties: > +- clock-frequency : frequency of bus clock in Hz > + Defaults to 100 KHz when the property is not specified > + > +Example: > + > +i2c0: i2c@113100 { > + compatible = "netlogic,xlp9xx-i2c"; > + #address-cells = <1>; > + #size-cells = <0>; > + reg = <0 0x113100 0x100>; > + clock-frequency = <400000>; > + interrupts = <30>; > + interrupt-parent = <&pic>; > +}; > diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig > index 22da9c2..dde4648 100644 > --- a/drivers/i2c/busses/Kconfig > +++ b/drivers/i2c/busses/Kconfig > @@ -898,6 +898,16 @@ config I2C_XLR > This driver can also be built as a module. If so, the module > will be called i2c-xlr. > > +config I2C_XLP9XX > + tristate "XLP9XX I2C support" > + depends on CPU_XLP || COMPILE_TEST > + help > + This driver enables support for the on-chip I2C interface of > + the Broadcom XLP9xx/XLP5xx MIPS processors. > + > + This driver can also be built as a module. If so, the module will > + be called i2c-xlp9xx. > + > config I2C_RCAR > tristate "Renesas R-Car I2C Controller" > depends on ARCH_SHMOBILE || COMPILE_TEST > diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile > index 3638feb..f8e0f0e 100644 > --- a/drivers/i2c/busses/Makefile > +++ b/drivers/i2c/busses/Makefile > @@ -87,6 +87,7 @@ obj-$(CONFIG_I2C_WMT) += i2c-wmt.o > obj-$(CONFIG_I2C_OCTEON) += i2c-octeon.o > obj-$(CONFIG_I2C_XILINX) += i2c-xiic.o > obj-$(CONFIG_I2C_XLR) += i2c-xlr.o > +obj-$(CONFIG_I2C_XLP9XX) += i2c-xlp9xx.o > obj-$(CONFIG_I2C_RCAR) += i2c-rcar.o > > # External I2C/SMBus adapter drivers > diff --git a/drivers/i2c/busses/i2c-xlp9xx.c b/drivers/i2c/busses/i2c-xlp9xx.c > new file mode 100644 > index 00000000..6886add > --- /dev/null > +++ b/drivers/i2c/busses/i2c-xlp9xx.c > @@ -0,0 +1,446 @@ > +/* > + * Copyright (c) 2003-2015 Broadcom Corporation > + * > + * 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. > + */ > + > +#include <linux/completion.h> > +#include <linux/errno.h> > +#include <linux/hardirq.h> > +#include <linux/i2c.h> > +#include <linux/init.h> > +#include <linux/interrupt.h> > +#include <linux/io.h> > +#include <linux/kernel.h> > +#include <linux/module.h> > +#include <linux/platform_device.h> > +#include <linux/slab.h> > + > +#define XLP9XX_I2C_DIV 0x0 > +#define XLP9XX_I2C_CTRL 0x1 > +#define XLP9XX_I2C_CMD 0x2 > +#define XLP9XX_I2C_STATUS 0x3 > +#define XLP9XX_I2C_MTXFIFO 0x4 > +#define XLP9XX_I2C_MRXFIFO 0x5 > +#define XLP9XX_I2C_MFIFOCTRL 0x6 > +#define XLP9XX_I2C_STXFIFO 0x7 > +#define XLP9XX_I2C_SRXFIFO 0x8 > +#define XLP9XX_I2C_SFIFOCTRL 0x9 > +#define XLP9XX_I2C_SLAVEADDR 0xA > +#define XLP9XX_I2C_OWNADDR 0xB > +#define XLP9XX_I2C_FIFOWCNT 0xC > +#define XLP9XX_I2C_INTEN 0xD > +#define XLP9XX_I2C_INTST 0xE > +#define XLP9XX_I2C_WAITCNT 0xF > +#define XLP9XX_I2C_TIMEOUT 0X10 > +#define XLP9XX_I2C_GENCALLADDR 0x11 > + > +#define XLP9XX_I2C_CTRL_MCTLEN_SHIFT 16 > +#define XLP9XX_I2C_MFIFOCTRL_HITH_SHIFT 8 > +#define XLP9XX_I2C_MFIFOCTRL_LOTH_SHIFT 0 > +#define XLP9XX_I2C_SLAVEADDR_ADDR_SHIFT 1 > + > +#define XLP9XX_I2C_CMD_START BIT(7) > +#define XLP9XX_I2C_CMD_STOP BIT(6) > +#define XLP9XX_I2C_CMD_READ BIT(5) > +#define XLP9XX_I2C_CMD_WRITE BIT(4) > +#define XLP9XX_I2C_CMD_ACK BIT(3) > + > +#define XLP9XX_I2C_CTRL_RST BIT(8) > +#define XLP9XX_I2C_CTRL_EN BIT(6) > +#define XLP9XX_I2C_CTRL_MASTER BIT(4) > +#define XLP9XX_I2C_CTRL_FIFORD BIT(1) > +#define XLP9XX_I2C_CTRL_ADDMODE BIT(0) > + > +#define XLP9XX_I2C_INTEN_NACKADDR BIT(25) > +#define XLP9XX_I2C_INTEN_SADDR BIT(13) > +#define XLP9XX_I2C_INTEN_DATADONE BIT(12) > +#define XLP9XX_I2C_INTEN_ARLOST BIT(11) > +#define XLP9XX_I2C_INTEN_MDATARDY BIT(5) > +#define XLP9XX_I2C_INTEN_MFIFOFULL BIT(4) > +#define XLP9XX_I2C_INTEN_MFIFOEMTY BIT(3) > +#define XLP9XX_I2C_INTEN_MFIFOHI BIT(2) > +#define XLP9XX_I2C_INTEN_BUSERR BIT(0) > + > +#define XLP9XX_I2C_MFIFOCTRL_RST BIT(16) > + > +#define XLP9XX_I2C_SLAVEADDR_RW BIT(0) > + > +#define XLP9XX_I2C_IP_CLK_FREQ 133000000UL > +#define XLP9XX_I2C_DEFAULT_FREQ 100000 > +#define XLP9XX_I2C_HIGH_FREQ 400000 > +#define XLP9XX_I2C_FIFO_SIZE 0x80U > +#define XLP9XX_I2C_TIMEOUT_MS 1000 > + > +#define XLP9XX_I2C_FIFO_WCNT_MASK 0xff > +#define XLP9XX_I2C_FIFO_CTRL_MASK 0xffff > +#define XLP9XX_I2C_STATUS_ERRMASK (XLP9XX_I2C_INTEN_ARLOST | \ > + XLP9XX_I2C_INTEN_NACKADDR | XLP9XX_I2C_INTEN_BUSERR) > + > +struct xlp9xx_i2c_dev { > + struct device *dev; > + struct i2c_adapter adapter; > + struct completion msg_complete; > + int irq; > + bool msg_read; > + u32 __iomem *base; > + u32 msg_buf_remaining; > + u32 msg_len; > + u32 clk_hz; > + u32 msg_err; > + u8 *msg_buf; > +}; > + > +static inline void xlp9xx_write_i2c_reg(struct xlp9xx_i2c_dev *priv, > + unsigned long reg, u32 val) > +{ > + writel(val, priv->base + reg); > +} > + > +static inline u32 xlp9xx_read_i2c_reg(struct xlp9xx_i2c_dev *priv, > + unsigned long reg) > +{ > + return readl(priv->base + reg); > +} > + > +static void xlp9xx_i2c_mask_irq(struct xlp9xx_i2c_dev *priv, u32 mask) > +{ > + mask = xlp9xx_read_i2c_reg(priv, XLP9XX_I2C_INTEN) & ~mask; > + xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_INTEN, mask); > +} > + > +static void xlp9xx_i2c_unmask_irq(struct xlp9xx_i2c_dev *priv, u32 mask) > +{ > + mask = xlp9xx_read_i2c_reg(priv, XLP9XX_I2C_INTEN) | mask; > + xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_INTEN, mask); > +} > + > +static void xlp9xx_i2c_set_rx_fifo_thres(struct xlp9xx_i2c_dev *priv, > + u32 th) > +{ > + xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_MFIFOCTRL, > + (th << XLP9XX_I2C_MFIFOCTRL_HITH_SHIFT)); > +} > + > +static void xlp9xx_i2c_fill_tx_fifo(struct xlp9xx_i2c_dev *priv) > +{ > + u32 len, i; > + u8 *buf = priv->msg_buf; > + > + len = min(priv->msg_buf_remaining, XLP9XX_I2C_FIFO_SIZE); > + for (i = 0; i < len; i++) > + xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_MTXFIFO, buf[i]); > + priv->msg_buf_remaining -= len; > + priv->msg_buf += len; > +} > + > +static void xlp9xx_i2c_drain_rx_fifo(struct xlp9xx_i2c_dev *priv) > +{ > + u32 len, i; > + u8 *buf = priv->msg_buf; > + > + len = xlp9xx_read_i2c_reg(priv, XLP9XX_I2C_FIFOWCNT) & > + XLP9XX_I2C_FIFO_WCNT_MASK; > + len = min(priv->msg_buf_remaining, len); > + for (i = 0; i < len; i++, buf++) > + *buf = xlp9xx_read_i2c_reg(priv, XLP9XX_I2C_MRXFIFO); > + > + priv->msg_buf_remaining -= len; > + priv->msg_buf = buf; > + > + if (priv->msg_buf_remaining) > + xlp9xx_i2c_set_rx_fifo_thres(priv, > + min(priv->msg_buf_remaining, XLP9XX_I2C_FIFO_SIZE)); > +} > + > +static irqreturn_t xlp9xx_i2c_isr(int irq, void *dev_id) > +{ > + struct xlp9xx_i2c_dev *priv = dev_id; > + u32 status; > + > + status = xlp9xx_read_i2c_reg(priv, XLP9XX_I2C_INTST); > + if (status == 0) > + return IRQ_NONE; > + > + xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_INTST, status); > + if (status & XLP9XX_I2C_STATUS_ERRMASK) { > + priv->msg_err = status; > + goto xfer_done; > + } > + > + /* SADDR ACK for SMBUS_QUICK */ > + if ((status & XLP9XX_I2C_INTEN_SADDR) && (priv->msg_len == 0)) > + goto xfer_done; > + > + if (!priv->msg_read) { > + /* TX FIFO got empty, fill it up again */ > + if (status & XLP9XX_I2C_INTEN_MFIFOEMTY) { > + if (priv->msg_buf_remaining) > + xlp9xx_i2c_fill_tx_fifo(priv); > + else > + xlp9xx_i2c_mask_irq(priv, > + XLP9XX_I2C_INTEN_MFIFOEMTY); > + } > + } else { > + /* data is in FIFO, read it */ > + if (status & (XLP9XX_I2C_INTEN_MDATARDY | > + XLP9XX_I2C_INTEN_DATADONE | > + XLP9XX_I2C_INTEN_MFIFOHI)) { > + if (status & XLP9XX_I2C_INTEN_MDATARDY) > + xlp9xx_i2c_mask_irq(priv, > + XLP9XX_I2C_INTEN_MDATARDY); > + if (priv->msg_buf_remaining) > + xlp9xx_i2c_drain_rx_fifo(priv); > + } > + } > + > + /* Transfer complete */ > + if (status & XLP9XX_I2C_INTEN_DATADONE) > + goto xfer_done; > + > + return IRQ_HANDLED; > + > +xfer_done: > + xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_INTEN, 0); > + complete(&priv->msg_complete); > + return IRQ_HANDLED; > +} > + > +static int xlp9xx_i2c_init(struct xlp9xx_i2c_dev *priv) > +{ > + u32 prescale; > + > + /* > + * The controller uses 5 * SCL clock internally. > + * So prescale value should be divided by 5. > + */ > + prescale = (((XLP9XX_I2C_IP_CLK_FREQ / priv->clk_hz) - 8) / 5) - 1; > + xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_CTRL, XLP9XX_I2C_CTRL_RST); > + xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_CTRL, XLP9XX_I2C_CTRL_EN | > + XLP9XX_I2C_CTRL_MASTER); > + xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_DIV, prescale); > + xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_INTEN, 0); > + > + return 0; > +} > + > +static int xlp9xx_i2c_xfer_msg(struct xlp9xx_i2c_dev *priv, struct i2c_msg *msg) > +{ > + int ret; > + u32 intr_mask, cmd, val; > + > + priv->msg_buf = msg->buf; > + priv->msg_buf_remaining = priv->msg_len = msg->len; > + priv->msg_err = 0; > + priv->msg_read = (msg->flags & I2C_M_RD); > + reinit_completion(&priv->msg_complete); > + > + /* Reset FIFO */ > + xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_MFIFOCTRL, > + XLP9XX_I2C_MFIFOCTRL_RST); > + > + /* set FIFO threshold if reading */ > + if (priv->msg_read) { > + val = min(priv->msg_buf_remaining, XLP9XX_I2C_FIFO_SIZE); > + xlp9xx_i2c_set_rx_fifo_thres(priv, val); > + } > + > + /* set slave addr */ > + xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_SLAVEADDR, > + (msg->addr << XLP9XX_I2C_SLAVEADDR_ADDR_SHIFT) | > + (priv->msg_read ? XLP9XX_I2C_SLAVEADDR_RW : 0)); > + > + /* Build control word for transfer */ > + val = xlp9xx_read_i2c_reg(priv, XLP9XX_I2C_CTRL); > + if (!priv->msg_read) > + val &= ~XLP9XX_I2C_CTRL_FIFORD; > + else > + val |= XLP9XX_I2C_CTRL_FIFORD; /* read */ > + if (msg->flags & I2C_M_TEN) > + val |= XLP9XX_I2C_CTRL_ADDMODE; /* 10-bit address mode*/ > + > + /* set data length to be transferred */ > + val = (val & XLP9XX_I2C_FIFO_CTRL_MASK) | > + (msg->len << XLP9XX_I2C_CTRL_MCTLEN_SHIFT); > + xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_CTRL, val); > + > + /* fill fifo during tx */ > + if (!priv->msg_read) > + xlp9xx_i2c_fill_tx_fifo(priv); > + > + /* set interrupt mask */ > + intr_mask = (XLP9XX_I2C_INTEN_ARLOST | XLP9XX_I2C_INTEN_BUSERR | > + XLP9XX_I2C_INTEN_NACKADDR | XLP9XX_I2C_INTEN_DATADONE); > + > + if (priv->msg_read) { > + intr_mask |= (XLP9XX_I2C_INTEN_MDATARDY | > + XLP9XX_I2C_INTEN_MFIFOHI); > + if (msg->len == 0) > + intr_mask |= XLP9XX_I2C_INTEN_SADDR; > + } else { > + if (msg->len == 0) > + intr_mask |= XLP9XX_I2C_INTEN_SADDR; > + else > + intr_mask |= XLP9XX_I2C_INTEN_MFIFOEMTY; > + } > + xlp9xx_i2c_unmask_irq(priv, intr_mask); > + > + /* set cmd reg */ > + cmd = XLP9XX_I2C_CMD_START | XLP9XX_I2C_CMD_STOP; > + cmd |= (priv->msg_read ? XLP9XX_I2C_CMD_READ : XLP9XX_I2C_CMD_WRITE); > + > + xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_CMD, cmd); > + > + ret = wait_for_completion_timeout(&priv->msg_complete, > + msecs_to_jiffies(XLP9XX_I2C_TIMEOUT_MS)); > + > + if (priv->msg_err) { > + dev_dbg(priv->dev, "transfer error %x!\n", priv->msg_err); > + if (priv->msg_err & XLP9XX_I2C_INTEN_BUSERR) > + xlp9xx_i2c_init(priv); > + return -EAGAIN; > + } > + > + if (ret == 0) { > + dev_dbg(priv->dev, "i2c transfer timed out!\n"); > + xlp9xx_i2c_init(priv); > + return -ETIMEDOUT; > + } > + > + return 0; > +} > + > +static int xlp9xx_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, > + int num) > +{ > + int i, ret; > + struct xlp9xx_i2c_dev *priv = i2c_get_adapdata(adap); > + > + for (i = 0; i < num; i++) { > + ret = xlp9xx_i2c_xfer_msg(priv, &msgs[i]); > + if (ret != 0) > + return ret; > + } > + > + return num; > +} > + > +static u32 xlp9xx_i2c_functionality(struct i2c_adapter *adapter) > +{ > + return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_I2C | > + I2C_FUNC_10BIT_ADDR; > +} > + > +static struct i2c_algorithm xlp9xx_i2c_algo = { > + .master_xfer = xlp9xx_i2c_xfer, > + .functionality = xlp9xx_i2c_functionality, > +}; > + > +static int xlp9xx_i2c_get_frequency(struct platform_device *pdev, > + struct xlp9xx_i2c_dev *priv) > +{ > + struct device_node *np = pdev->dev.of_node; > + u32 freq; > + int err; > + > + err = of_property_read_u32(np, "clock-frequency", &freq); > + if (err) { > + dev_dbg(&pdev->dev, "using default frequency %u\n", freq); > + freq = XLP9XX_I2C_DEFAULT_FREQ; > + } else if (freq == 0 || freq > XLP9XX_I2C_HIGH_FREQ) { > + dev_warn(&pdev->dev, "invalid frequency %u, using default\n", > + freq); > + freq = XLP9XX_I2C_DEFAULT_FREQ; > + } > + priv->clk_hz = freq; > + > + return 0; > +} > + > +static int xlp9xx_i2c_probe(struct platform_device *pdev) > +{ > + struct xlp9xx_i2c_dev *priv; > + struct resource *res; > + int err = 0; > + > + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); > + if (!priv) > + return -ENOMEM; > + > + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > + priv->base = devm_ioremap_resource(&pdev->dev, res); > + if (IS_ERR(priv->base)) > + return PTR_ERR(priv->base); > + > + priv->irq = platform_get_irq(pdev, 0); > + if (priv->irq <= 0) { > + dev_err(&pdev->dev, "invalid irq!\n"); > + return priv->irq; > + } > + > + xlp9xx_i2c_get_frequency(pdev, priv); > + xlp9xx_i2c_init(priv); > + > + err = devm_request_irq(&pdev->dev, priv->irq, xlp9xx_i2c_isr, 0, > + pdev->name, priv); > + if (err) { > + dev_err(&pdev->dev, "IRQ request failed!\n"); > + return err; > + } > + > + init_completion(&priv->msg_complete); > + priv->adapter.dev.parent = &pdev->dev; > + priv->adapter.algo = &xlp9xx_i2c_algo; > + priv->adapter.dev.of_node = pdev->dev.of_node; > + priv->dev = &pdev->dev; > + > + snprintf(priv->adapter.name, sizeof(priv->adapter.name), "xlp9xx-i2c"); > + i2c_set_adapdata(&priv->adapter, priv); > + > + err = i2c_add_adapter(&priv->adapter); > + if (err) { > + dev_err(&pdev->dev, "failed to add I2C:%d adapter!\n", > + pdev->id); > + return err; > + } > + > + platform_set_drvdata(pdev, priv); > + dev_dbg(&pdev->dev, "I2C bus:%d added\n", priv->adapter.nr); > + > + return 0; > +} > + > +static int xlp9xx_i2c_remove(struct platform_device *pdev) > +{ > + struct xlp9xx_i2c_dev *priv; > + > + priv = platform_get_drvdata(pdev); > + xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_INTEN, 0); > + synchronize_irq(priv->irq); > + i2c_del_adapter(&priv->adapter); > + xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_CTRL, 0); > + > + return 0; > +} > + > +static const struct of_device_id xlp9xx_i2c_of_match[] = { > + { .compatible = "netlogic,xlp9xx-i2c", }, > + { /* sentinel */ }, > +}; > + > +static struct platform_driver xlp9xx_i2c_driver = { > + .probe = xlp9xx_i2c_probe, > + .remove = xlp9xx_i2c_remove, > + .driver = { > + .name = "xlp9xx-i2c", > + .of_match_table = xlp9xx_i2c_of_match, > + }, > +}; > + > +module_platform_driver(xlp9xx_i2c_driver); > + > +MODULE_AUTHOR("Subhendu Sekhar Behera <sbehera@xxxxxxxxxxxx>"); > +MODULE_DESCRIPTION("XLP9XX/5XX I2C Bus Controller Driver"); > +MODULE_LICENSE("GPL v2"); > This now looks fine to me. Thanks! Reviewed-by: Ray Jui <rjui@xxxxxxxxxxxx> -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html