[PATCH v2 13/14] mfd: zl3073x: Load mfg file into HW if it is present

Ivan Vecera
2025-04-09T14:44:05Z

Add support for loading mfg file that can be provided by a user. The mfg
file can be generated by Microchip tool and contains snippets of device
configuration that is different from the one stored in the flash memory
inside the chip.

Signed-off-by: Ivan Vecera <ivecera@redhat.com>
---
drivers/mfd/zl3073x-core.c | 110 +++++++++++++++++++++++++++++++++++++
1 file changed, 110 insertions(+)

diff --git a/drivers/mfd/zl3073x-core.c b/drivers/mfd/zl3073x-core.c
index a1fb5af5b3d9f..110071b28cab9 100644
--- a/drivers/mfd/zl3073x-core.c
+++ b/drivers/mfd/zl3073x-core.c
@@ -4,15 +4,19 @@
#include <linux/bitfield.h>
#include <linux/bits.h>
#include <linux/cleanup.h>
+#include <linux/delay.h>
#include <linux/dev_printk.h>
#include <linux/device.h>
#include <linux/export.h>
+#include <linux/firmware.h>
+#include <linux/kstrtox.h>
#include <linux/lockdep.h>
#include <linux/mfd/zl3073x.h>
#include <linux/module.h>
#include <linux/netlink.h>
#include <linux/regmap.h>
#include <linux/sprintf.h>
+#include <linux/string.h>
#include <linux/unaligned.h>
#include <net/devlink.h>
#include "zl3073x.h"
@@ -464,6 +468,108 @@ static void zl3073x_devlink_unregister(void *ptr)
devlink_unregister(ptr);
}

+static int zl3073x_fw_parse_line(struct zl3073x_dev *zldev, const char *line)
+{
+#define ZL3073X_FW_WHITESPACES_SIZE 3
+#define ZL3073X_FW_COMMAND_SIZE 1
+ const char *ptr = line;
+ char *endp;
+ u32 delay;
+ u16 addr;
+ u8 val;
+
+ switch (ptr[0]) {
+ case 'X':
+ /* The line looks like this:
+ * X , ADDR , VAL
+ * Where:
+ * - X means that is a command that needs to be executed
+ * - ADDR represents the addr and is always 2 bytes and the
+ * value is in hex, for example 0x0232
+ * - VAL represents the value that is written and is always 1
+ * byte and the value is in hex, for example 0x12
+ */
+ ptr += ZL3073X_FW_COMMAND_SIZE;
+ ptr += ZL3073X_FW_WHITESPACES_SIZE;
+ addr = simple_strtoul(ptr, &endp, 16);
+
+ ptr = endp;
+ ptr += ZL3073X_FW_WHITESPACES_SIZE;
+ val = simple_strtoul(ptr, NULL, 16);
+
+ /* Write requested value to given register */
+ return zl3073x_write_reg(zldev, addr, 1, &val);
+ case 'W':
+ /* The line looks like this:
+ * W , DELAY
+ * Where:
+ * - W means that is a wait command
+ * - DELAY represents the delay in microseconds and the value
+ * is in decimal
+ */
+ ptr += ZL3073X_FW_COMMAND_SIZE;
+ ptr += ZL3073X_FW_WHITESPACES_SIZE;
+ delay = simple_strtoul(ptr, NULL, 10);
+
+ fsleep(delay);
+ break;
+ default:
+ break;
+ }
+
+ return 0;
+}
+
+#define ZL3073X_MFG_FILE "microchip/zl3073x.mfg"
+
+static void zl3073x_fw_load(struct zl3073x_dev *zldev)
+{
+ const struct firmware *fw;
+ const char *ptr, *end;
+ char buf[128];
+ int rc;
+
+ rc = firmware_request_nowarn(&fw, ZL3073X_MFG_FILE, zldev->dev);
+ if (rc)
+ return;
+
+ dev_info(zldev->dev, "Applying mfg file %s...\n", ZL3073X_MFG_FILE);
+
+ guard(zl3073x)(zldev);
+
+ ptr = fw->data;
+ end = ptr + fw->size;
+ while (ptr < end) {
+ /* Get next end of the line or end of buffer */
+ char *eol = strnchrnul(ptr, end - ptr, '\n');
+ size_t len = eol - ptr;
+
+ /* Check line length */
+ if (len >= sizeof(buf)) {
+ dev_err(zldev->dev, "Line in firmware is too long\n");
+ return;
+ }
+
+ /* Copy line from buffer */
+ memcpy(buf, ptr, len);
+ buf[len] = '\0';
+
+ /* Parse and process the line */
+ rc = zl3073x_fw_parse_line(zldev, buf);
+ if (rc) {
+ dev_err(zldev->dev,
+ "Failed to parse firmware line: %pe\n",
+ ERR_PTR(rc));
+ break;
+ }
+
+ /* Move to next line */
+ ptr = eol + 1;
+ }
+
+ release_firmware(fw);
+}
+
/**
* zl3073x_dev_init - initialize zl3073x device
* @zldev: pointer to zl3073x device
@@ -505,6 +611,9 @@ int zl3073x_dev_init(struct zl3073x_dev *zldev, u8 dev_id)
/* Use chip ID and given dev ID as clock ID */
zldev->clock_id = ((u64)id << 8) | dev_id;

+ /* Load mfg file if present */
+ zl3073x_fw_load(zldev);
+
dev_info(zldev->dev, "ChipID(%X), ChipRev(%X), FwVer(%u)\n",
id, revision, fw_ver);
dev_info(zldev->dev, "Custom config version: %lu.%lu.%lu.%lu\n",
@@ -528,3 +637,4 @@ EXPORT_SYMBOL_NS_GPL(zl3073x_dev_init, "ZL3073X");
MODULE_AUTHOR("Ivan Vecera <ivecera@redhat.com>");
MODULE_DESCRIPTION("Microchip ZL3073x core driver");
MODULE_LICENSE("GPL");
+MODULE_FIRMWARE(ZL3073X_MFG_FILE);
--
2.48.1