summaryrefslogtreecommitdiffstats
path: root/drivers/misc/ics932s401.c
diff options
context:
space:
mode:
authorAdrian Betschart <adrian.betschart@cinemaone.ch>2026-09-11 17:13:14 +0200
committerAlex Deucher <alexander.deucher@amd.com>2026-10-01 17:18:05 -0400
commit106b4a2a78b2a2f14885604891957b84bba502db (patch)
tree5d40eef2428fb1a4791ab46a4b19091a5910eac2 /drivers/misc/ics932s401.c
downloadlinux-stable-106b4a2a78b2a2f14885604891957b84bba502db.tar.gz
linux-stable-106b4a2a78b2a2f14885604891957b84bba502db.zip
drm/amd/display: Try RGB before YCbCr 4:4:4 in stream validationgrafted
amdgpu_dm_create_validate_stream_for_sink() walks encoding_order[] and uses the first encoding that validates. YCbCr 4:4:4 is listed before RGB, so an HDMI sink that advertises 4:4:4 gets YCbCr 4:4:4 whenever the "color format" property is left at AUTO, even though RGB fits the same link. That contradicts the documented AUTO behaviour for HDMI in enum drm_connector_color_format (RGB, falling back to YCbCr 4:2:0 only when the bandwidth is not available or the mode is 4:2:0-only), which the amdgpu implementation of the property also describes. It also leaves the "Broadcast RGB" property without effect on such sinks, since the quantization range it selects only applies to RGB output. Try RGB first. The mask still holds every encoding the sink supports, so a mode that cannot carry RGB falls back exactly as before. For reference, v7.2 picked RGB here unless YCbCr 4:4:4 was forced through debugfs, while earlier kernels picked YCbCr 4:4:4 for any HDMI sink that advertised it. Fixes: 0b0ff65d3ca1 ("drm/amd/display: Refactor stream validation") Suggested-by: Adolfo Rodrigues <adolfotregosa@gmail.com> Assisted-by: Claude Code:claude-fable-5-1 Signed-off-by: Adrian Betschart <adrian.betschart@cinemaone.ch> Reviewed-by: Fangzhi Zuo <jerry.zuo@amd.com> Tested-by: Adolfo Rodrigues <adolfotregosa@gmail.com> Tested-by: Daniel Wheeler <daniel.wheeler@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> (cherry picked from commit 7de432bc753133764dc40d37f9388da56de251e7)
Diffstat (limited to 'drivers/misc/ics932s401.c')
-rw-r--r--drivers/misc/ics932s401.c481
1 files changed, 481 insertions, 0 deletions
diff --git a/drivers/misc/ics932s401.c b/drivers/misc/ics932s401.c
new file mode 100644
index 000000000..e8bcf0df2
--- /dev/null
+++ b/drivers/misc/ics932s401.c
@@ -0,0 +1,481 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * A driver for the Integrated Circuits ICS932S401
+ * Copyright (C) 2008 IBM
+ *
+ * Author: Darrick J. Wong <darrick.wong@oracle.com>
+ */
+
+#include <linux/module.h>
+#include <linux/jiffies.h>
+#include <linux/i2c.h>
+#include <linux/err.h>
+#include <linux/mutex.h>
+#include <linux/delay.h>
+#include <linux/log2.h>
+#include <linux/slab.h>
+
+/* Addresses to scan */
+static const unsigned short normal_i2c[] = { 0x69, I2C_CLIENT_END };
+
+/* ICS932S401 registers */
+#define ICS932S401_REG_CFG2 0x01
+#define ICS932S401_CFG1_SPREAD 0x01
+#define ICS932S401_REG_CFG7 0x06
+#define ICS932S401_FS_MASK 0x07
+#define ICS932S401_REG_VENDOR_REV 0x07
+#define ICS932S401_VENDOR 1
+#define ICS932S401_VENDOR_MASK 0x0F
+#define ICS932S401_REV 4
+#define ICS932S401_REV_SHIFT 4
+#define ICS932S401_REG_DEVICE 0x09
+#define ICS932S401_DEVICE 11
+#define ICS932S401_REG_CTRL 0x0A
+#define ICS932S401_MN_ENABLED 0x80
+#define ICS932S401_CPU_ALT 0x04
+#define ICS932S401_SRC_ALT 0x08
+#define ICS932S401_REG_CPU_M_CTRL 0x0B
+#define ICS932S401_M_MASK 0x3F
+#define ICS932S401_REG_CPU_N_CTRL 0x0C
+#define ICS932S401_REG_CPU_SPREAD1 0x0D
+#define ICS932S401_REG_CPU_SPREAD2 0x0E
+#define ICS932S401_SPREAD_MASK 0x7FFF
+#define ICS932S401_REG_SRC_M_CTRL 0x0F
+#define ICS932S401_REG_SRC_N_CTRL 0x10
+#define ICS932S401_REG_SRC_SPREAD1 0x11
+#define ICS932S401_REG_SRC_SPREAD2 0x12
+#define ICS932S401_REG_CPU_DIVISOR 0x13
+#define ICS932S401_CPU_DIVISOR_SHIFT 4
+#define ICS932S401_REG_PCISRC_DIVISOR 0x14
+#define ICS932S401_SRC_DIVISOR_MASK 0x0F
+#define ICS932S401_PCI_DIVISOR_SHIFT 4
+
+/* Base clock is 14.318MHz */
+#define BASE_CLOCK 14318
+
+#define NUM_REGS 21
+#define NUM_MIRRORED_REGS 15
+
+static int regs_to_copy[NUM_MIRRORED_REGS] = {
+ ICS932S401_REG_CFG2,
+ ICS932S401_REG_CFG7,
+ ICS932S401_REG_VENDOR_REV,
+ ICS932S401_REG_DEVICE,
+ ICS932S401_REG_CTRL,
+ ICS932S401_REG_CPU_M_CTRL,
+ ICS932S401_REG_CPU_N_CTRL,
+ ICS932S401_REG_CPU_SPREAD1,
+ ICS932S401_REG_CPU_SPREAD2,
+ ICS932S401_REG_SRC_M_CTRL,
+ ICS932S401_REG_SRC_N_CTRL,
+ ICS932S401_REG_SRC_SPREAD1,
+ ICS932S401_REG_SRC_SPREAD2,
+ ICS932S401_REG_CPU_DIVISOR,
+ ICS932S401_REG_PCISRC_DIVISOR,
+};
+
+/* How often do we reread sensors values? (In jiffies) */
+#define SENSOR_REFRESH_INTERVAL (2 * HZ)
+
+/* How often do we reread sensor limit values? (In jiffies) */
+#define LIMIT_REFRESH_INTERVAL (60 * HZ)
+
+struct ics932s401_data {
+ struct attribute_group attrs;
+ struct mutex lock;
+ char sensors_valid;
+ unsigned long sensors_last_updated; /* In jiffies */
+
+ u8 regs[NUM_REGS];
+};
+
+static int ics932s401_probe(struct i2c_client *client);
+static int ics932s401_detect(struct i2c_client *client,
+ struct i2c_board_info *info);
+static void ics932s401_remove(struct i2c_client *client);
+
+static const struct i2c_device_id ics932s401_id[] = {
+ { .name = "ics932s401" },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, ics932s401_id);
+
+static struct i2c_driver ics932s401_driver = {
+ .class = I2C_CLASS_HWMON,
+ .driver = {
+ .name = "ics932s401",
+ },
+ .probe = ics932s401_probe,
+ .remove = ics932s401_remove,
+ .id_table = ics932s401_id,
+ .detect = ics932s401_detect,
+ .address_list = normal_i2c,
+};
+
+static struct ics932s401_data *ics932s401_update_device(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct ics932s401_data *data = i2c_get_clientdata(client);
+ unsigned long local_jiffies = jiffies;
+ int i, temp;
+
+ mutex_lock(&data->lock);
+ if (time_before(local_jiffies, data->sensors_last_updated +
+ SENSOR_REFRESH_INTERVAL)
+ && data->sensors_valid)
+ goto out;
+
+ /*
+ * Each register must be read as a word and then right shifted 8 bits.
+ * Not really sure why this is; setting the "byte count programming"
+ * register to 1 does not fix this problem.
+ */
+ for (i = 0; i < NUM_MIRRORED_REGS; i++) {
+ temp = i2c_smbus_read_word_data(client, regs_to_copy[i]);
+ if (temp < 0)
+ temp = 0;
+ data->regs[regs_to_copy[i]] = temp >> 8;
+ }
+
+ data->sensors_last_updated = local_jiffies;
+ data->sensors_valid = 1;
+
+out:
+ mutex_unlock(&data->lock);
+ return data;
+}
+
+static ssize_t show_spread_enabled(struct device *dev,
+ struct device_attribute *devattr,
+ char *buf)
+{
+ struct ics932s401_data *data = ics932s401_update_device(dev);
+
+ if (data->regs[ICS932S401_REG_CFG2] & ICS932S401_CFG1_SPREAD)
+ return sprintf(buf, "1\n");
+
+ return sprintf(buf, "0\n");
+}
+
+/* bit to cpu khz map */
+static const int fs_speeds[] = {
+ 266666,
+ 133333,
+ 200000,
+ 166666,
+ 333333,
+ 100000,
+ 400000,
+ 0,
+};
+
+/* clock divisor map */
+static const int divisors[] = {2, 3, 5, 15, 4, 6, 10, 30, 8, 12, 20, 60, 16,
+ 24, 40, 120};
+
+/* Calculate CPU frequency from the M/N registers. */
+static int calculate_cpu_freq(struct ics932s401_data *data)
+{
+ int m, n, freq;
+
+ m = data->regs[ICS932S401_REG_CPU_M_CTRL] & ICS932S401_M_MASK;
+ n = data->regs[ICS932S401_REG_CPU_N_CTRL];
+
+ /* Pull in bits 8 & 9 from the M register */
+ n |= ((int)data->regs[ICS932S401_REG_CPU_M_CTRL] & 0x80) << 1;
+ n |= ((int)data->regs[ICS932S401_REG_CPU_M_CTRL] & 0x40) << 3;
+
+ freq = BASE_CLOCK * (n + 8) / (m + 2);
+ freq /= divisors[data->regs[ICS932S401_REG_CPU_DIVISOR] >>
+ ICS932S401_CPU_DIVISOR_SHIFT];
+
+ return freq;
+}
+
+static ssize_t show_cpu_clock(struct device *dev,
+ struct device_attribute *devattr,
+ char *buf)
+{
+ struct ics932s401_data *data = ics932s401_update_device(dev);
+
+ return sprintf(buf, "%d\n", calculate_cpu_freq(data));
+}
+
+static ssize_t show_cpu_clock_sel(struct device *dev,
+ struct device_attribute *devattr,
+ char *buf)
+{
+ struct ics932s401_data *data = ics932s401_update_device(dev);
+ int freq;
+
+ if (data->regs[ICS932S401_REG_CTRL] & ICS932S401_MN_ENABLED)
+ freq = calculate_cpu_freq(data);
+ else {
+ /* Freq is neatly wrapped up for us */
+ int fid = data->regs[ICS932S401_REG_CFG7] & ICS932S401_FS_MASK;
+
+ freq = fs_speeds[fid];
+ if (data->regs[ICS932S401_REG_CTRL] & ICS932S401_CPU_ALT) {
+ switch (freq) {
+ case 166666:
+ freq = 160000;
+ break;
+ case 333333:
+ freq = 320000;
+ break;
+ }
+ }
+ }
+
+ return sprintf(buf, "%d\n", freq);
+}
+
+/* Calculate SRC frequency from the M/N registers. */
+static int calculate_src_freq(struct ics932s401_data *data)
+{
+ int m, n, freq;
+
+ m = data->regs[ICS932S401_REG_SRC_M_CTRL] & ICS932S401_M_MASK;
+ n = data->regs[ICS932S401_REG_SRC_N_CTRL];
+
+ /* Pull in bits 8 & 9 from the M register */
+ n |= ((int)data->regs[ICS932S401_REG_SRC_M_CTRL] & 0x80) << 1;
+ n |= ((int)data->regs[ICS932S401_REG_SRC_M_CTRL] & 0x40) << 3;
+
+ freq = BASE_CLOCK * (n + 8) / (m + 2);
+ freq /= divisors[data->regs[ICS932S401_REG_PCISRC_DIVISOR] &
+ ICS932S401_SRC_DIVISOR_MASK];
+
+ return freq;
+}
+
+static ssize_t show_src_clock(struct device *dev,
+ struct device_attribute *devattr,
+ char *buf)
+{
+ struct ics932s401_data *data = ics932s401_update_device(dev);
+
+ return sprintf(buf, "%d\n", calculate_src_freq(data));
+}
+
+static ssize_t show_src_clock_sel(struct device *dev,
+ struct device_attribute *devattr,
+ char *buf)
+{
+ struct ics932s401_data *data = ics932s401_update_device(dev);
+ int freq;
+
+ if (data->regs[ICS932S401_REG_CTRL] & ICS932S401_MN_ENABLED)
+ freq = calculate_src_freq(data);
+ else
+ /* Freq is neatly wrapped up for us */
+ if (data->regs[ICS932S401_REG_CTRL] & ICS932S401_CPU_ALT &&
+ data->regs[ICS932S401_REG_CTRL] & ICS932S401_SRC_ALT)
+ freq = 96000;
+ else
+ freq = 100000;
+
+ return sprintf(buf, "%d\n", freq);
+}
+
+/* Calculate PCI frequency from the SRC M/N registers. */
+static int calculate_pci_freq(struct ics932s401_data *data)
+{
+ int m, n, freq;
+
+ m = data->regs[ICS932S401_REG_SRC_M_CTRL] & ICS932S401_M_MASK;
+ n = data->regs[ICS932S401_REG_SRC_N_CTRL];
+
+ /* Pull in bits 8 & 9 from the M register */
+ n |= ((int)data->regs[ICS932S401_REG_SRC_M_CTRL] & 0x80) << 1;
+ n |= ((int)data->regs[ICS932S401_REG_SRC_M_CTRL] & 0x40) << 3;
+
+ freq = BASE_CLOCK * (n + 8) / (m + 2);
+ freq /= divisors[data->regs[ICS932S401_REG_PCISRC_DIVISOR] >>
+ ICS932S401_PCI_DIVISOR_SHIFT];
+
+ return freq;
+}
+
+static ssize_t show_pci_clock(struct device *dev,
+ struct device_attribute *devattr,
+ char *buf)
+{
+ struct ics932s401_data *data = ics932s401_update_device(dev);
+
+ return sprintf(buf, "%d\n", calculate_pci_freq(data));
+}
+
+static ssize_t show_pci_clock_sel(struct device *dev,
+ struct device_attribute *devattr,
+ char *buf)
+{
+ struct ics932s401_data *data = ics932s401_update_device(dev);
+ int freq;
+
+ if (data->regs[ICS932S401_REG_CTRL] & ICS932S401_MN_ENABLED)
+ freq = calculate_pci_freq(data);
+ else
+ freq = 33333;
+
+ return sprintf(buf, "%d\n", freq);
+}
+
+static ssize_t show_value(struct device *dev,
+ struct device_attribute *devattr,
+ char *buf);
+
+static ssize_t show_spread(struct device *dev,
+ struct device_attribute *devattr,
+ char *buf);
+
+static DEVICE_ATTR(spread_enabled, S_IRUGO, show_spread_enabled, NULL);
+static DEVICE_ATTR(cpu_clock_selection, S_IRUGO, show_cpu_clock_sel, NULL);
+static DEVICE_ATTR(cpu_clock, S_IRUGO, show_cpu_clock, NULL);
+static DEVICE_ATTR(src_clock_selection, S_IRUGO, show_src_clock_sel, NULL);
+static DEVICE_ATTR(src_clock, S_IRUGO, show_src_clock, NULL);
+static DEVICE_ATTR(pci_clock_selection, S_IRUGO, show_pci_clock_sel, NULL);
+static DEVICE_ATTR(pci_clock, S_IRUGO, show_pci_clock, NULL);
+static DEVICE_ATTR(usb_clock, S_IRUGO, show_value, NULL);
+static DEVICE_ATTR(ref_clock, S_IRUGO, show_value, NULL);
+static DEVICE_ATTR(cpu_spread, S_IRUGO, show_spread, NULL);
+static DEVICE_ATTR(src_spread, S_IRUGO, show_spread, NULL);
+
+static struct attribute *ics932s401_attr[] = {
+ &dev_attr_spread_enabled.attr,
+ &dev_attr_cpu_clock_selection.attr,
+ &dev_attr_cpu_clock.attr,
+ &dev_attr_src_clock_selection.attr,
+ &dev_attr_src_clock.attr,
+ &dev_attr_pci_clock_selection.attr,
+ &dev_attr_pci_clock.attr,
+ &dev_attr_usb_clock.attr,
+ &dev_attr_ref_clock.attr,
+ &dev_attr_cpu_spread.attr,
+ &dev_attr_src_spread.attr,
+ NULL
+};
+
+static ssize_t show_value(struct device *dev,
+ struct device_attribute *devattr,
+ char *buf)
+{
+ int x;
+
+ if (devattr == &dev_attr_usb_clock)
+ x = 48000;
+ else if (devattr == &dev_attr_ref_clock)
+ x = BASE_CLOCK;
+ else
+ BUG();
+
+ return sprintf(buf, "%d\n", x);
+}
+
+static ssize_t show_spread(struct device *dev,
+ struct device_attribute *devattr,
+ char *buf)
+{
+ struct ics932s401_data *data = ics932s401_update_device(dev);
+ int reg;
+ unsigned long val;
+
+ if (!(data->regs[ICS932S401_REG_CFG2] & ICS932S401_CFG1_SPREAD))
+ return sprintf(buf, "0%%\n");
+
+ if (devattr == &dev_attr_src_spread)
+ reg = ICS932S401_REG_SRC_SPREAD1;
+ else if (devattr == &dev_attr_cpu_spread)
+ reg = ICS932S401_REG_CPU_SPREAD1;
+ else
+ BUG();
+
+ val = data->regs[reg] | (data->regs[reg + 1] << 8);
+ val &= ICS932S401_SPREAD_MASK;
+
+ /* Scale 0..2^14 to -0.5. */
+ val = 500000 * val / 16384;
+ return sprintf(buf, "-0.%lu%%\n", val);
+}
+
+/* Return 0 if detection is successful, -ENODEV otherwise */
+static int ics932s401_detect(struct i2c_client *client,
+ struct i2c_board_info *info)
+{
+ struct i2c_adapter *adapter = client->adapter;
+ int vendor, device, revision;
+
+ if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
+ return -ENODEV;
+
+ vendor = i2c_smbus_read_word_data(client, ICS932S401_REG_VENDOR_REV);
+ vendor >>= 8;
+ revision = vendor >> ICS932S401_REV_SHIFT;
+ vendor &= ICS932S401_VENDOR_MASK;
+ if (vendor != ICS932S401_VENDOR)
+ return -ENODEV;
+
+ device = i2c_smbus_read_word_data(client, ICS932S401_REG_DEVICE);
+ device >>= 8;
+ if (device != ICS932S401_DEVICE)
+ return -ENODEV;
+
+ if (revision != ICS932S401_REV)
+ dev_info(&adapter->dev, "Unknown revision %d\n", revision);
+
+ strscpy(info->type, "ics932s401", I2C_NAME_SIZE);
+
+ return 0;
+}
+
+static int ics932s401_probe(struct i2c_client *client)
+{
+ struct ics932s401_data *data;
+ int err;
+
+ data = kzalloc_obj(struct ics932s401_data);
+ if (!data) {
+ err = -ENOMEM;
+ goto exit;
+ }
+
+ i2c_set_clientdata(client, data);
+ mutex_init(&data->lock);
+
+ dev_info(&client->dev, "%s chip found\n", client->name);
+
+ /* Register sysfs hooks */
+ data->attrs.attrs = ics932s401_attr;
+ err = sysfs_create_group(&client->dev.kobj, &data->attrs);
+ if (err)
+ goto exit_free;
+
+ return 0;
+
+exit_free:
+ kfree(data);
+exit:
+ return err;
+}
+
+static void ics932s401_remove(struct i2c_client *client)
+{
+ struct ics932s401_data *data = i2c_get_clientdata(client);
+
+ sysfs_remove_group(&client->dev.kobj, &data->attrs);
+ kfree(data);
+}
+
+module_i2c_driver(ics932s401_driver);
+
+MODULE_AUTHOR("Darrick J. Wong <darrick.wong@oracle.com>");
+MODULE_DESCRIPTION("ICS932S401 driver");
+MODULE_LICENSE("GPL");
+
+/* IBM IntelliStation Z30 */
+MODULE_ALIAS("dmi:bvnIBM:*:rn9228:*");
+MODULE_ALIAS("dmi:bvnIBM:*:rn9232:*");
+
+/* IBM x3650/x3550 */
+MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3650*");
+MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3550*");