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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
commit4352b8aee98005853aa63f57d6377282de17a33f (patch)
tree27614d7a9ef05c32d089004e104364ce42324837 /lib/cmdline.c
downloadlinux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz
linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni: "A new driver this cycle, for the AMD AXI I3C controller. There are also new features such as IBI wakeup support, SETAASA device discovery and ACPI support for the the DAA methods, meaning we can now communicate with the SPD devices on DDR5 modules. New driver: - AMD AXI I3C master controller Subsystem: - I3C Common Command Code (CCC) handling improvements, especially around GET CCCs - SETAASA device discovery support - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as well as I2C devices on I3C bus - IBI-based wakeup support Drivers: - dw: SETAASA support - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C controller support, PIO queue management support for HCI v1.2 - renesas: improve suspend to RAM support, add runtime PM support" * tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits) i3c: dw: reduce do_daa time if there's no client i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2 i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode i3c: dw: rename "pclk" to "apb" to match dt-binding i3c: dw: make struct dw_i3c_cmd smaller i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding i3c: renesas: Don't register devices when ENTDAA times out i3c: master: dw-i3c-master: fix OD timing for first broadcast i3c: mipi-i3c-hci: Advertise IBI wakeup capability i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev() i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI i3c: master: Reject IBI requests from non-IBI-capable devices i3c: master: Add helper to query bus wakeup requirements i3c: master: Report wakeup events for IBIs i3c: master: Support IBI-based wakeup capability i3c: master: Fix potential UAF in i3c_device_match() i3c: master: Fix potential UAF in i3c_device_uevent() i3c: Make dev->desc locking assumptions explicit i3c: master: Fix use-after-free of master->this ...
Diffstat (limited to 'lib/cmdline.c')
-rw-r--r--lib/cmdline.c285
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diff --git a/lib/cmdline.c b/lib/cmdline.c
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index 000000000..16cce6621
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+++ b/lib/cmdline.c
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+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * linux/lib/cmdline.c
+ * Helper functions generally used for parsing kernel command line
+ * and module options.
+ *
+ * Code and copyrights come from init/main.c and arch/i386/kernel/setup.c.
+ *
+ * GNU Indent formatting options for this file: -kr -i8 -npsl -pcs
+ */
+
+#include <linux/export.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/ctype.h>
+
+/*
+ * If a hyphen was found in get_option, this will handle the
+ * range of numbers, M-N. This will expand the range and insert
+ * the values[M, M+1, ..., N] into the ints array in get_options.
+ */
+
+static int get_range(char **str, int *pint, int n)
+{
+ int x, inc_counter, upper_range;
+
+ (*str)++;
+ upper_range = simple_strtol((*str), NULL, 0);
+ inc_counter = upper_range - *pint;
+ for (x = *pint; n && x < upper_range; x++, n--)
+ *pint++ = x;
+ return inc_counter;
+}
+
+/**
+ * get_option - Parse integer from an option string
+ * @str: option string
+ * @pint: (optional output) integer value parsed from @str
+ *
+ * Read an int from an option string; if available accept a subsequent
+ * comma as well.
+ *
+ * When @pint is NULL the function can be used as a validator of
+ * the current option in the string.
+ *
+ * Return:
+ * 0 - no int in string
+ * 1 - int found, no subsequent comma
+ * 2 - int found including a subsequent comma
+ * 3 - hyphen found to denote a range
+ *
+ * Leading hyphen without integer is no integer case, but we consume it
+ * for the sake of simplification.
+ */
+
+int get_option(char **str, int *pint)
+{
+ char *cur = *str;
+ int value;
+
+ if (!cur || !(*cur))
+ return 0;
+ if (*cur == '-')
+ value = -simple_strtoull(++cur, str, 0);
+ else
+ value = simple_strtoull(cur, str, 0);
+ if (pint)
+ *pint = value;
+ if (cur == *str)
+ return 0;
+ if (**str == ',') {
+ (*str)++;
+ return 2;
+ }
+ if (**str == '-')
+ return 3;
+
+ return 1;
+}
+EXPORT_SYMBOL(get_option);
+
+/**
+ * get_options - Parse a string into a list of integers
+ * @str: String to be parsed
+ * @nints: size of integer array
+ * @ints: integer array (must have room for at least one element)
+ *
+ * This function parses a string containing a comma-separated
+ * list of integers, a hyphen-separated range of _positive_ integers,
+ * or a combination of both. The parse halts when the array is
+ * full, or when no more numbers can be retrieved from the
+ * string.
+ *
+ * When @nints is 0, the function just validates the given @str and
+ * returns the amount of parseable integers as described below.
+ *
+ * Returns:
+ *
+ * The first element is filled by the number of collected integers
+ * in the range. The rest is what was parsed from the @str.
+ *
+ * Return value is the character in the string which caused
+ * the parse to end (typically a null terminator, if @str is
+ * completely parseable).
+ */
+
+char *get_options(const char *str, int nints, int *ints)
+{
+ bool validate = (nints == 0);
+ int res, i = 1;
+
+ while (i < nints || validate) {
+ int *pint = validate ? ints : ints + i;
+
+ res = get_option((char **)&str, pint);
+ if (res == 0)
+ break;
+ if (res == 3) {
+ int n = validate ? 0 : nints - i;
+ int range_nums;
+
+ range_nums = get_range((char **)&str, pint, n);
+ if (range_nums < 0)
+ break;
+ /*
+ * Decrement the result by one to leave out the
+ * last number in the range. The next iteration
+ * will handle the upper number in the range
+ */
+ i += (range_nums - 1);
+ }
+ i++;
+ if (res == 1)
+ break;
+ }
+ ints[0] = i - 1;
+ return (char *)str;
+}
+EXPORT_SYMBOL(get_options);
+
+/**
+ * memparse - parse a string with mem suffixes into a number
+ * @ptr: Where parse begins
+ * @retptr: (output) Optional pointer to next char after parse completes
+ *
+ * Parses a string into a number. The number stored at @ptr is
+ * potentially suffixed with K, M, G, T, P, E.
+ *
+ * Return: The value as recognized by simple_strtoull() multiplied
+ * by the value as specified by suffix, if any.
+ */
+
+unsigned long long memparse(const char *ptr, char **retptr)
+{
+ char *endptr; /* local pointer to end of parsed string */
+ unsigned long long ret = simple_strtoull(ptr, &endptr, 0);
+ unsigned int shl = 0;
+
+ /* Consume valid suffix even in case of overflow. */
+ switch (*endptr) {
+ case 'E':
+ case 'e':
+ shl += 10;
+ fallthrough;
+ case 'P':
+ case 'p':
+ shl += 10;
+ fallthrough;
+ case 'T':
+ case 't':
+ shl += 10;
+ fallthrough;
+ case 'G':
+ case 'g':
+ shl += 10;
+ fallthrough;
+ case 'M':
+ case 'm':
+ shl += 10;
+ fallthrough;
+ case 'K':
+ case 'k':
+ shl += 10;
+ fallthrough;
+ default:
+ break;
+ }
+
+ if (shl && likely(ptr != endptr)) {
+ /* Have valid suffix with preceding number. */
+ if (unlikely(check_shl_overflow(ret, shl, &ret)))
+ ret = ULLONG_MAX;
+ endptr++;
+ }
+
+ if (retptr)
+ *retptr = endptr;
+
+ return ret;
+}
+EXPORT_SYMBOL(memparse);
+
+/**
+ * parse_option_str - Parse a string and check an option is set or not
+ * @str: String to be parsed
+ * @option: option name
+ *
+ * This function parses a string containing a comma-separated list of
+ * strings like a=b,c.
+ *
+ * Return: True if there's such option in the string or false otherwise.
+ */
+bool parse_option_str(const char *str, const char *option)
+{
+ while (*str) {
+ if (!strncmp(str, option, strlen(option))) {
+ str += strlen(option);
+ if (!*str || *str == ',')
+ return true;
+ }
+
+ while (*str && *str != ',')
+ str++;
+
+ if (*str == ',')
+ str++;
+ }
+
+ return false;
+}
+
+/*
+ * Parse a string to get a param value pair.
+ * You can use " around spaces, but can't escape ".
+ * Hyphens and underscores equivalent in parameter names.
+ */
+char *next_arg(char *args, char **param, char **val)
+{
+ unsigned int i, equals = 0;
+ int in_quote = 0, quoted = 0;
+
+ if (*args == '"') {
+ args++;
+ in_quote = 1;
+ quoted = 1;
+ }
+
+ for (i = 0; args[i]; i++) {
+ if (isspace(args[i]) && !in_quote)
+ break;
+ if (equals == 0) {
+ if (args[i] == '=')
+ equals = i;
+ }
+ if (args[i] == '"')
+ in_quote = !in_quote;
+ }
+
+ *param = args;
+ if (!equals)
+ *val = NULL;
+ else {
+ args[equals] = '\0';
+ *val = args + equals + 1;
+
+ /* Don't include quotes in value. */
+ if (**val == '"') {
+ (*val)++;
+ if (args[i-1] == '"')
+ args[i-1] = '\0';
+ }
+ }
+ if (quoted && i > 0 && args[i-1] == '"')
+ args[i-1] = '\0';
+
+ if (args[i]) {
+ args[i] = '\0';
+ args += i + 1;
+ } else
+ args += i;
+
+ /* Chew up trailing spaces. */
+ return skip_spaces(args);
+}
+EXPORT_SYMBOL(next_arg);