Update the PCI driver to generate ACPI information so that Linux has the full information about each I2C bus.
Signed-off-by: Simon Glass sjg@chromium.org
---
drivers/i2c/designware_i2c.c | 25 ++++++++ drivers/i2c/designware_i2c.h | 15 +++++ drivers/i2c/designware_i2c_pci.c | 104 ++++++++++++++++++++++++++++++- 3 files changed, 143 insertions(+), 1 deletion(-)
diff --git a/drivers/i2c/designware_i2c.c b/drivers/i2c/designware_i2c.c index 9933391bdb..af9ad124d3 100644 --- a/drivers/i2c/designware_i2c.c +++ b/drivers/i2c/designware_i2c.c @@ -298,6 +298,31 @@ static int _dw_i2c_set_bus_speed(struct dw_i2c *priv, struct i2c_regs *i2c_base, /* Restore back i2c now speed set */ if (ena == IC_ENABLE_0B) dw_i2c_enable(i2c_base, true); + if (priv) + priv->config = config; + return 0; +} + +int dw_i2c_gen_speed_config(const struct udevice *dev, int speed_hz, + struct dw_i2c_speed_config *config) +{ + struct dw_i2c *priv = dev_get_priv(dev); + ulong rate; + int ret; + + if (CONFIG_IS_ENABLED(CLK)) { + rate = clk_get_rate(&priv->clk); + if (IS_ERR_VALUE(rate)) + return log_msg_ret("clk", -EINVAL); + } else { + rate = IC_CLK; + } + + ret = calc_bus_speed(priv, speed_hz, rate, config); + if (ret) + printf("%s: ret=%d\n", __func__, ret); + if (ret) + return log_msg_ret("calc_bus_speed", ret);
return 0; } diff --git a/drivers/i2c/designware_i2c.h b/drivers/i2c/designware_i2c.h index be17f00140..03657ea3ab 100644 --- a/drivers/i2c/designware_i2c.h +++ b/drivers/i2c/designware_i2c.h @@ -198,6 +198,7 @@ struct dw_i2c { #if CONFIG_IS_ENABLED(CLK) struct clk clk; #endif + struct dw_i2c_speed_config config; };
extern const struct dm_i2c_ops designware_i2c_ops; @@ -206,4 +207,18 @@ int designware_i2c_probe(struct udevice *bus); int designware_i2c_remove(struct udevice *dev); int designware_i2c_ofdata_to_platdata(struct udevice *bus);
+/** + * dw_i2c_gen_speed_config() - Calculate config info from requested speed1 + * + * Calculate the speed config from the given @speed_hz and return it so that + * it can be incorporated in ACPI tables + * + * @dev: I2C bus to check + * @speed_hz: Requested speed in Hz + * @config: Returns config to use for that speed + * @return 0 if OK, -ve on error + */ +int dw_i2c_gen_speed_config(const struct udevice *dev, int speed_hz, + struct dw_i2c_speed_config *config); + #endif /* __DW_I2C_H_ */ diff --git a/drivers/i2c/designware_i2c_pci.c b/drivers/i2c/designware_i2c_pci.c index 50f03e3d90..4fc918c955 100644 --- a/drivers/i2c/designware_i2c_pci.c +++ b/drivers/i2c/designware_i2c_pci.c @@ -6,9 +6,14 @@ */
#include <common.h> +#include <acpigen.h> +#include <acpi_device.h> #include <dm.h> #include <spl.h> #include <asm/lpss.h> +#include <dm/acpi.h> +#include <dm/device-internal.h> +#include <dm/uclass-internal.h> #include "designware_i2c.h"
enum { @@ -86,6 +91,8 @@ static int designware_i2c_pci_bind(struct udevice *dev) { char name[20];
+ if (dev_of_valid(dev)) + return 0; /* * Create a unique device name for PCI type devices * ToDo: @@ -99,13 +106,107 @@ static int designware_i2c_pci_bind(struct udevice *dev) * be possible. We cannot use static data in drivers since they may be * used in SPL or before relocation. */ - dev->req_seq = gd->arch.dw_i2c_num_cards++; + dev->req_seq = uclass_find_next_free_req_seq(UCLASS_I2C); sprintf(name, "i2c_designware#%u", dev->req_seq); device_set_name(dev, name);
return 0; }
+/* + * Write ACPI object to describe speed configuration. + * + * ACPI Object: Name ("xxxx", Package () { scl_lcnt, scl_hcnt, sda_hold } + * + * SSCN: I2C_SPEED_STANDARD + * FMCN: I2C_SPEED_FAST + * FPCN: I2C_SPEED_FAST_PLUS + * HSCN: I2C_SPEED_HIGH + */ +static void dw_i2c_acpi_write_speed_config(struct acpi_ctx *ctx, + struct dw_i2c_speed_config *config) +{ + switch (config->speed_mode) { + case IC_SPEED_MODE_HIGH: + acpigen_write_name(ctx, "HSCN"); + break; + case IC_SPEED_MODE_FAST_PLUS: + acpigen_write_name(ctx, "FPCN"); + break; + case IC_SPEED_MODE_FAST: + acpigen_write_name(ctx, "FMCN"); + break; + case IC_SPEED_MODE_STANDARD: + default: + acpigen_write_name(ctx, "SSCN"); + } + + /* Package () { scl_lcnt, scl_hcnt, sda_hold } */ + acpigen_write_package(ctx, 3); + acpigen_write_word(ctx, config->scl_hcnt); + acpigen_write_word(ctx, config->scl_lcnt); + acpigen_write_dword(ctx, config->sda_hold); + acpigen_pop_len(ctx); +} + +/* + * Generate I2C timing information into the SSDT for the OS driver to consume, + * optionally applying override values provided by the caller. + */ +static int dw_i2c_acpi_fill_ssdt(const struct udevice *dev, + struct acpi_ctx *ctx) +{ + struct dw_i2c_speed_config config; + char path[ACPI_PATH_MAX]; + u32 speeds[4]; + int size, i; + int ret; + + /* If no device-tree node, ignore this since we assume it isn't used */ + if (!dev_of_valid(dev)) + return 0; + ret = acpi_device_path(dev, path, sizeof(path)); + if (ret) + return log_msg_ret("path", ret); + + size = dev_read_size(dev, "i2c,speeds"); + if (size < 0) + return log_msg_ret("i2c,speeds", -EINVAL); + size /= sizeof(u32); + if (size > ARRAY_SIZE(speeds)) + return log_msg_ret("array", -E2BIG); + + ret = dev_read_u32_array(dev, "i2c,speeds", speeds, size); + if (ret) + return log_msg_ret("read", -E2BIG); + + if (0) { + acpigen_write_scope(ctx, path); + for (i = 0; i < size; i++) { + ret = dw_i2c_gen_speed_config(dev, speeds[i], &config); + if (ret) + return log_msg_ret("config", ret); + dw_i2c_acpi_write_speed_config(ctx, &config); + } + } else { + uint speed; + + speed = dev_read_u32_default(dev, "clock-frequency", 100000); + acpigen_write_scope(ctx, path); + ret = dw_i2c_gen_speed_config(dev, speed, &config); + if (ret) + return log_msg_ret("config", ret); + dw_i2c_acpi_write_speed_config(ctx, &config); + } + acpigen_pop_len(ctx); + + return 0; +} + +struct acpi_ops dw_i2c_acpi_ops = { + .fill_ssdt = dw_i2c_acpi_fill_ssdt, +}; + static const struct udevice_id designware_i2c_pci_ids[] = { { .compatible = "snps,designware-i2c-pci" }, { .compatible = "intel,apl-i2c", .data = INTEL_APL }, @@ -123,6 +224,7 @@ U_BOOT_DRIVER(i2c_designware_pci) = { .remove = designware_i2c_remove, .flags = DM_FLAG_OS_PREPARE, .ops = &designware_i2c_ops, + acpi_ops_ptr(&dw_i2c_acpi_ops) };
static struct pci_device_id designware_pci_supported[] = {