| Message ID | 20240229-mbly-i2c-v2-9-b32ed18c098c@bootlin.com |
|---|---|
| State | New |
| Headers | show |
| Series | [v2,01/11] dt-bindings: i2c: nomadik: add mobileye,eyeq5-i2c bindings and example | expand |
Hi Theo, ... > +#include <linux/amba/bus.h> > #include <linux/bitfield.h> > +#include <linux/clk.h> > +#include <linux/err.h> > +#include <linux/i2c.h> > #include <linux/init.h> > -#include <linux/module.h> > -#include <linux/amba/bus.h> > -#include <linux/slab.h> > #include <linux/interrupt.h> > -#include <linux/i2c.h> > -#include <linux/err.h> > -#include <linux/clk.h> > #include <linux/io.h> > -#include <linux/pm_runtime.h> > +#include <linux/mfd/syscon.h> > +#include <linux/module.h> > #include <linux/of.h> > #include <linux/pinctrl/consumer.h> > +#include <linux/pm_runtime.h> > +#include <linux/regmap.h> > +#include <linux/slab.h> Please reorder the headers in a different patch. > #define DRIVER_NAME "nmk-i2c" > ... > +static inline u8 nmk_i2c_readb(const struct nmk_i2c_dev *priv, > + unsigned long reg) > +{ > + if (priv->has_32b_bus) > + return readl(priv->virtbase + reg); > + else > + return readb(priv->virtbase + reg); nit: no need for the else (your choice though, if you want to have ti coherent with the write counterpart). > +} > + > +static inline void nmk_i2c_writeb(const struct nmk_i2c_dev *priv, u32 val, > + unsigned long reg) > +{ > + if (priv->has_32b_bus) > + writel(val, priv->virtbase + reg); > + else > + writeb(val, priv->virtbase + reg); > +} ... > +static int nmk_i2c_eyeq5_probe(struct nmk_i2c_dev *priv) > +{ > + struct device *dev = &priv->adev->dev; > + struct device_node *np = dev->of_node; > + unsigned int shift, speed_mode; > + struct regmap *olb; > + unsigned int id; > + > + priv->has_32b_bus = true; > + > + olb = syscon_regmap_lookup_by_phandle_args(np, "mobileye,olb", 1, &id); > + if (IS_ERR_OR_NULL(olb)) { > + if (!olb) > + olb = ERR_PTR(-ENOENT); > + return dev_err_probe(dev, PTR_ERR(olb), > + "failed OLB lookup: %lu\n", PTR_ERR(olb)); just return PTR_ERR(olb) and use dev_err_probe() in the upper layer probe. > + } > + > + if (priv->clk_freq <= 400000) > + speed_mode = 0b00; > + else if (priv->clk_freq <= 1000000) > + speed_mode = 0b01; > + else > + speed_mode = 0b10; would be nice to have these as defines. > + > + shift = NMK_I2C_EYEQ5_OLB_IOCR2_SHIFT(id); > + regmap_update_bits(olb, NMK_I2C_EYEQ5_OLB_IOCR2, > + 0b11 << shift, speed_mode << shift); please define these values and for hexadecimals use 0x... > + return 0; > +} > + > static int nmk_i2c_probe(struct amba_device *adev, const struct amba_id *id) > { > int ret = 0; > @@ -1001,8 +1065,17 @@ static int nmk_i2c_probe(struct amba_device *adev, const struct amba_id *id) > > priv->vendor = vendor; > priv->adev = adev; > + priv->has_32b_bus = false; > nmk_i2c_of_probe(np, priv); > > + if (of_device_is_compatible(np, "mobileye,eyeq5-i2c")) { > + ret = nmk_i2c_eyeq5_probe(priv); > + if (ret) { > + dev_info(dev, "%s: %d: %d\n", __func__, __LINE__, ret); > + return ret; > + } as said above, use dev_err_probe here. Andi > + } > + > if (priv->tft > max_fifo_threshold) { > dev_warn(dev, "requested TX FIFO threshold %u, adjusted down to %u\n", > priv->tft, max_fifo_threshold); > > -- > 2.44.0 >
Hello, On Mon Mar 4, 2024 at 3:08 PM CET, Andi Shyti wrote: > Hi Theo, > > ... > > > +#include <linux/amba/bus.h> > > #include <linux/bitfield.h> > > +#include <linux/clk.h> > > +#include <linux/err.h> > > +#include <linux/i2c.h> > > #include <linux/init.h> > > -#include <linux/module.h> > > -#include <linux/amba/bus.h> > > -#include <linux/slab.h> > > #include <linux/interrupt.h> > > -#include <linux/i2c.h> > > -#include <linux/err.h> > > -#include <linux/clk.h> > > #include <linux/io.h> > > -#include <linux/pm_runtime.h> > > +#include <linux/mfd/syscon.h> > > +#include <linux/module.h> > > #include <linux/of.h> > > #include <linux/pinctrl/consumer.h> > > +#include <linux/pm_runtime.h> > > +#include <linux/regmap.h> > > +#include <linux/slab.h> > > Please reorder the headers in a different patch. Will do. > > > #define DRIVER_NAME "nmk-i2c" > > > > ... > > > +static inline u8 nmk_i2c_readb(const struct nmk_i2c_dev *priv, > > + unsigned long reg) > > +{ > > + if (priv->has_32b_bus) > > + return readl(priv->virtbase + reg); > > + else > > + return readb(priv->virtbase + reg); > > nit: no need for the else (your choice though, if you want to > have ti coherent with the write counterpart). Indeed, the useless else block can be removed. Will do. > > +} > > + > > +static inline void nmk_i2c_writeb(const struct nmk_i2c_dev *priv, u32 val, > > + unsigned long reg) > > +{ > > + if (priv->has_32b_bus) > > + writel(val, priv->virtbase + reg); > > + else > > + writeb(val, priv->virtbase + reg); > > +} > > ... > > > +static int nmk_i2c_eyeq5_probe(struct nmk_i2c_dev *priv) > > +{ > > + struct device *dev = &priv->adev->dev; > > + struct device_node *np = dev->of_node; > > + unsigned int shift, speed_mode; > > + struct regmap *olb; > > + unsigned int id; > > + > > + priv->has_32b_bus = true; > > + > > + olb = syscon_regmap_lookup_by_phandle_args(np, "mobileye,olb", 1, &id); > > + if (IS_ERR_OR_NULL(olb)) { > > + if (!olb) > > + olb = ERR_PTR(-ENOENT); > > + return dev_err_probe(dev, PTR_ERR(olb), > > + "failed OLB lookup: %lu\n", PTR_ERR(olb)); > > just return PTR_ERR(olb) and use dev_err_probe() in the upper > layer probe. Good catch. In previous revisions nmk_i2c_eyeq5_probe() had multiple error cases so it had to be the one doing the logging. Now that there is a single possible error parent can do it. It should simplify code. > > > + } > > + > > + if (priv->clk_freq <= 400000) > > + speed_mode = 0b00; > > + else if (priv->clk_freq <= 1000000) > > + speed_mode = 0b01; > > + else > > + speed_mode = 0b10; > > would be nice to have these as defines. Agreed. Will be named based on I2C mode names, eg standard, fast, high speed, fast plus. > > > + > > + shift = NMK_I2C_EYEQ5_OLB_IOCR2_SHIFT(id); > > + regmap_update_bits(olb, NMK_I2C_EYEQ5_OLB_IOCR2, > > + 0b11 << shift, speed_mode << shift); > > please define these values and for hexadecimals use 0x... 0b11 is a two-bit mask. What do you mean by "these values"? Something like: #define NMK_I2C_EYEQ5_SPEED_MODE_FAST 0b00 #define NMK_I2C_EYEQ5_SPEED_MODE_FAST_PLUS 0b01 #define NMK_I2C_EYEQ5_SPEED_MODE_HIGH_SPEED 0b10 static const u8 nmk_i2c_eyeq5_masks[] = { [0] = 0x0030, [1] = 0x00C0, [2] = 0x0300, [3] = 0x0C00, [4] = 0x3000, }; static int nmk_i2c_eyeq5_probe(struct nmk_i2c_dev *priv) { // ... unsigned int id, mask, speed_mode; priv->has_32b_bus = true; olb = syscon_regmap_lookup_by_phandle_args(np, "mobileye,olb", 1, &id); // TODO: olb error checking // TODO: check id is valid if (priv->clk_freq <= 400000) speed_mode = NMK_I2C_EYEQ5_SPEED_MODE_FAST; else if (priv->clk_freq <= 1000000) speed_mode = NMK_I2C_EYEQ5_SPEED_MODE_FAST_PLUS; else speed_mode = NMK_I2C_EYEQ5_SPEED_MODE_HIGH_SPEED; mask = nmk_i2c_eyeq5_masks[id]; regmap_update_bits(olb, NMK_I2C_EYEQ5_OLB_IOCR2, mask, speed_mode << __fls(mask)); return 0; } Else I do not see what you are suggesting by "please define these values". Have a nice day, -- Théo Lebrun, Bootlin Embedded Linux and Kernel engineering https://bootlin.com
diff --git a/drivers/i2c/busses/i2c-nomadik.c b/drivers/i2c/busses/i2c-nomadik.c index 2d3247979e45..e9a77377add4 100644 --- a/drivers/i2c/busses/i2c-nomadik.c +++ b/drivers/i2c/busses/i2c-nomadik.c @@ -6,22 +6,30 @@ * I2C master mode controller driver, used in Nomadik 8815 * and Ux500 platforms. * + * The Mobileye EyeQ5 platform is also supported; it uses + * the same Ux500/DB8500 IP block with two quirks: + * - The memory bus only supports 32-bit accesses. + * - A register must be configured for the I2C speed mode; + * it is located in a shared register region called OLB. + * * Author: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com> * Author: Sachin Verma <sachin.verma@st.com> */ +#include <linux/amba/bus.h> #include <linux/bitfield.h> +#include <linux/clk.h> +#include <linux/err.h> +#include <linux/i2c.h> #include <linux/init.h> -#include <linux/module.h> -#include <linux/amba/bus.h> -#include <linux/slab.h> #include <linux/interrupt.h> -#include <linux/i2c.h> -#include <linux/err.h> -#include <linux/clk.h> #include <linux/io.h> -#include <linux/pm_runtime.h> +#include <linux/mfd/syscon.h> +#include <linux/module.h> #include <linux/of.h> #include <linux/pinctrl/consumer.h> +#include <linux/pm_runtime.h> +#include <linux/regmap.h> +#include <linux/slab.h> #define DRIVER_NAME "nmk-i2c" @@ -110,6 +118,10 @@ enum i2c_freq_mode { I2C_FREQ_MODE_FAST_PLUS, /* up to 1 Mb/s */ }; +/* Mobileye EyeQ5 offset into a shared register region (called OLB) */ +#define NMK_I2C_EYEQ5_OLB_IOCR2 0x0B8 +#define NMK_I2C_EYEQ5_OLB_IOCR2_SHIFT(id) (4 + 2 * (id)) + /** * struct i2c_vendor_data - per-vendor variations * @has_mtdws: variant has the MTDWS bit @@ -168,6 +180,7 @@ struct i2c_nmk_client { * @xfer_wq: xfer done wait queue. * @xfer_done: xfer done boolean. * @result: controller propogated result. + * @has_32b_bus: controller is on a bus that only supports 32-bit accesses. */ struct nmk_i2c_dev { struct i2c_vendor_data *vendor; @@ -186,6 +199,7 @@ struct nmk_i2c_dev { struct wait_queue_head xfer_wq; bool xfer_done; int result; + bool has_32b_bus; }; /* controller's abort causes */ @@ -209,6 +223,24 @@ static inline void i2c_clr_bit(void __iomem *reg, u32 mask) writel(readl(reg) & ~mask, reg); } +static inline u8 nmk_i2c_readb(const struct nmk_i2c_dev *priv, + unsigned long reg) +{ + if (priv->has_32b_bus) + return readl(priv->virtbase + reg); + else + return readb(priv->virtbase + reg); +} + +static inline void nmk_i2c_writeb(const struct nmk_i2c_dev *priv, u32 val, + unsigned long reg) +{ + if (priv->has_32b_bus) + writel(val, priv->virtbase + reg); + else + writeb(val, priv->virtbase + reg); +} + /** * flush_i2c_fifo() - This function flushes the I2C FIFO * @priv: private data of I2C Driver @@ -514,7 +546,7 @@ static void fill_tx_fifo(struct nmk_i2c_dev *priv, int no_bytes) (priv->cli.count != 0); count--) { /* write to the Tx FIFO */ - writeb(*priv->cli.buffer, priv->virtbase + I2C_TFR); + nmk_i2c_writeb(priv, *priv->cli.buffer, I2C_TFR); priv->cli.buffer++; priv->cli.count--; priv->cli.xfer_bytes++; @@ -783,7 +815,7 @@ static irqreturn_t i2c_irq_handler(int irq, void *arg) case I2C_IT_RXFNF: for (count = rft; count > 0; count--) { /* Read the Rx FIFO */ - *priv->cli.buffer = readb(priv->virtbase + I2C_RFR); + *priv->cli.buffer = nmk_i2c_readb(priv, I2C_RFR); priv->cli.buffer++; } priv->cli.count -= rft; @@ -793,7 +825,7 @@ static irqreturn_t i2c_irq_handler(int irq, void *arg) /* Rx FIFO full */ case I2C_IT_RXFF: for (count = MAX_I2C_FIFO_THRESHOLD; count > 0; count--) { - *priv->cli.buffer = readb(priv->virtbase + I2C_RFR); + *priv->cli.buffer = nmk_i2c_readb(priv, I2C_RFR); priv->cli.buffer++; } priv->cli.count -= MAX_I2C_FIFO_THRESHOLD; @@ -809,7 +841,7 @@ static irqreturn_t i2c_irq_handler(int irq, void *arg) if (priv->cli.count == 0) break; *priv->cli.buffer = - readb(priv->virtbase + I2C_RFR); + nmk_i2c_readb(priv, I2C_RFR); priv->cli.buffer++; priv->cli.count--; priv->cli.xfer_bytes++; @@ -985,6 +1017,38 @@ static void nmk_i2c_of_probe(struct device_node *np, priv->timeout_usecs = 200 * USEC_PER_MSEC; } +static int nmk_i2c_eyeq5_probe(struct nmk_i2c_dev *priv) +{ + struct device *dev = &priv->adev->dev; + struct device_node *np = dev->of_node; + unsigned int shift, speed_mode; + struct regmap *olb; + unsigned int id; + + priv->has_32b_bus = true; + + olb = syscon_regmap_lookup_by_phandle_args(np, "mobileye,olb", 1, &id); + if (IS_ERR_OR_NULL(olb)) { + if (!olb) + olb = ERR_PTR(-ENOENT); + return dev_err_probe(dev, PTR_ERR(olb), + "failed OLB lookup: %lu\n", PTR_ERR(olb)); + } + + if (priv->clk_freq <= 400000) + speed_mode = 0b00; + else if (priv->clk_freq <= 1000000) + speed_mode = 0b01; + else + speed_mode = 0b10; + + shift = NMK_I2C_EYEQ5_OLB_IOCR2_SHIFT(id); + regmap_update_bits(olb, NMK_I2C_EYEQ5_OLB_IOCR2, + 0b11 << shift, speed_mode << shift); + + return 0; +} + static int nmk_i2c_probe(struct amba_device *adev, const struct amba_id *id) { int ret = 0; @@ -1001,8 +1065,17 @@ static int nmk_i2c_probe(struct amba_device *adev, const struct amba_id *id) priv->vendor = vendor; priv->adev = adev; + priv->has_32b_bus = false; nmk_i2c_of_probe(np, priv); + if (of_device_is_compatible(np, "mobileye,eyeq5-i2c")) { + ret = nmk_i2c_eyeq5_probe(priv); + if (ret) { + dev_info(dev, "%s: %d: %d\n", __func__, __LINE__, ret); + return ret; + } + } + if (priv->tft > max_fifo_threshold) { dev_warn(dev, "requested TX FIFO threshold %u, adjusted down to %u\n", priv->tft, max_fifo_threshold);
Add compatible for the integration of the same DB8500 IP block into the Mobileye EyeQ5 platform. Two quirks are present: - The memory bus only supports 32-bit accesses. Avoid writeb() and readb() by introducing helper functions that fallback to writel() and readl(). - A register must be configured for the I2C speed mode; it is located in a shared register region called OLB. We access that memory region using a syscon & regmap that gets passed as a phandle (mobileye,olb). A two-bit enum per controller is written into the register; that requires us to know the global index of the I2C controller (cell arg to the mobileye,olb phandle). We add #include <linux/mfd/syscon.h> and <linux/regmap.h> and sort headers. Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com> --- drivers/i2c/busses/i2c-nomadik.c | 95 +++++++++++++++++++++++++++++++++++----- 1 file changed, 84 insertions(+), 11 deletions(-)