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	 b2108fc82a
			
		
	
	
		b2108fc82a
		
	
	
	
	
		
			
			Other subsystem(s) may want to reuse the for_each_if() macro. Move it to util_macros.h to make it globally available. Suggested-by: Bartosz Golaszewski <brgl@bgdev.pl> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Jani Nikula <jani.nikula@intel.com> Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/20250213182527.3092371-2-andriy.shevchenko@linux.intel.com Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
		
			
				
	
	
		
			94 lines
		
	
	
	
		
			2.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			94 lines
		
	
	
	
		
			2.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* SPDX-License-Identifier: GPL-2.0 */
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| #ifndef _LINUX_HELPER_MACROS_H_
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| #define _LINUX_HELPER_MACROS_H_
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| 
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| #include <linux/math.h>
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| 
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| /**
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|  * for_each_if - helper for handling conditionals in various for_each macros
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|  * @condition: The condition to check
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|  *
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|  * Typical use::
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|  *
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|  *	#define for_each_foo_bar(x, y) \'
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|  *		list_for_each_entry(x, y->list, head) \'
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|  *			for_each_if(x->something == SOMETHING)
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|  *
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|  * The for_each_if() macro makes the use of for_each_foo_bar() less error
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|  * prone.
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|  */
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| #define for_each_if(condition) if (!(condition)) {} else
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| 
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| /**
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|  * find_closest - locate the closest element in a sorted array
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|  * @x: The reference value.
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|  * @a: The array in which to look for the closest element. Must be sorted
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|  *  in ascending order.
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|  * @as: Size of 'a'.
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|  *
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|  * Returns the index of the element closest to 'x'.
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|  * Note: If using an array of negative numbers (or mixed positive numbers),
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|  *       then be sure that 'x' is of a signed-type to get good results.
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|  */
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| #define find_closest(x, a, as)						\
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| ({									\
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| 	typeof(as) __fc_i, __fc_as = (as) - 1;				\
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| 	long __fc_mid_x, __fc_x = (x);					\
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| 	long __fc_left, __fc_right;					\
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| 	typeof(*a) const *__fc_a = (a);					\
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| 	for (__fc_i = 0; __fc_i < __fc_as; __fc_i++) {			\
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| 		__fc_mid_x = (__fc_a[__fc_i] + __fc_a[__fc_i + 1]) / 2;	\
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| 		if (__fc_x <= __fc_mid_x) {				\
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| 			__fc_left = __fc_x - __fc_a[__fc_i];		\
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| 			__fc_right = __fc_a[__fc_i + 1] - __fc_x;	\
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| 			if (__fc_right < __fc_left)			\
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| 				__fc_i++;				\
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| 			break;						\
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| 		}							\
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| 	}								\
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| 	(__fc_i);							\
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| })
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| 
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| /**
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|  * find_closest_descending - locate the closest element in a sorted array
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|  * @x: The reference value.
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|  * @a: The array in which to look for the closest element. Must be sorted
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|  *  in descending order.
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|  * @as: Size of 'a'.
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|  *
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|  * Similar to find_closest() but 'a' is expected to be sorted in descending
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|  * order. The iteration is done in reverse order, so that the comparison
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|  * of '__fc_right' & '__fc_left' also works for unsigned numbers.
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|  */
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| #define find_closest_descending(x, a, as)				\
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| ({									\
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| 	typeof(as) __fc_i, __fc_as = (as) - 1;				\
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| 	long __fc_mid_x, __fc_x = (x);					\
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| 	long __fc_left, __fc_right;					\
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| 	typeof(*a) const *__fc_a = (a);					\
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| 	for (__fc_i = __fc_as; __fc_i >= 1; __fc_i--) {			\
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| 		__fc_mid_x = (__fc_a[__fc_i] + __fc_a[__fc_i - 1]) / 2;	\
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| 		if (__fc_x <= __fc_mid_x) {				\
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| 			__fc_left = __fc_x - __fc_a[__fc_i];		\
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| 			__fc_right = __fc_a[__fc_i - 1] - __fc_x;	\
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| 			if (__fc_right < __fc_left)			\
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| 				__fc_i--;				\
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| 			break;						\
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| 		}							\
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| 	}								\
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| 	(__fc_i);							\
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| })
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| 
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| /**
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|  * is_insidevar - check if the @ptr points inside the @var memory range.
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|  * @ptr:	the pointer to a memory address.
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|  * @var:	the variable which address and size identify the memory range.
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|  *
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|  * Evaluates to true if the address in @ptr lies within the memory
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|  * range allocated to @var.
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|  */
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| #define is_insidevar(ptr, var)						\
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| 	((uintptr_t)(ptr) >= (uintptr_t)(var) &&			\
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| 	 (uintptr_t)(ptr) <  (uintptr_t)(var) + sizeof(var))
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| 
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| #endif
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