[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / usb / core / buffer.c

/*
 * DMA memory management for framework level HCD code (hc_driver)
 *
 * This implementation plugs in through generic "usb_bus" level methods,
 * and should work with all USB controllers, regardles of bus type.
 */

#include <linux/config.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/device.h>
#include <linux/mm.h>
#include <asm/io.h>
#include <asm/scatterlist.h>
#include <linux/dma-mapping.h>
#include <linux/dmapool.h>


#ifdef CONFIG_USB_DEBUG
	#define DEBUG
#else
	#undef DEBUG
#endif

#include <linux/usb.h>
#include "hcd.h"


/*
 * DMA-Coherent Buffers
 */

/* FIXME tune these based on pool statistics ... */
static const size_t	pool_max [HCD_BUFFER_POOLS] = {
	/* platforms without dma-friendly caches might need to
	 * prevent cacheline sharing...
	 */
	32,
	128,
	512,
	PAGE_SIZE / 2
	/* bigger --> allocate pages */
};


/* SETUP primitives */

/**
 * hcd_buffer_create - initialize buffer pools
 * @hcd: the bus whose buffer pools are to be initialized
 * Context: !in_interrupt()
 *
 * Call this as part of initializing a host controller that uses the dma
 * memory allocators.  It initializes some pools of dma-coherent memory that
 * will be shared by all drivers using that controller, or returns a negative
 * errno value on error.
 *
 * Call hcd_buffer_destroy() to clean up after using those pools.
 */
int hcd_buffer_create (struct usb_hcd *hcd)
{
	char		name [16];
	int 		i, size;

	for (i = 0; i < HCD_BUFFER_POOLS; i++) { 
		if (!(size = pool_max [i]))
			continue;
		snprintf (name, sizeof name, "buffer-%d", size);
		hcd->pool [i] = dma_pool_create (name, hcd->self.controller,
				size, size, 0);
		if (!hcd->pool [i]) {
			hcd_buffer_destroy (hcd);
			return -ENOMEM;
		}
	}
	return 0;
}


/**
 * hcd_buffer_destroy - deallocate buffer pools
 * @hcd: the bus whose buffer pools are to be destroyed
 * Context: !in_interrupt()
 *
 * This frees the buffer pools created by hcd_buffer_create().
 */
void hcd_buffer_destroy (struct usb_hcd *hcd)
{
	int		i;

	for (i = 0; i < HCD_BUFFER_POOLS; i++) { 
		struct dma_pool		*pool = hcd->pool [i];
		if (pool) {
			dma_pool_destroy (pool);
			hcd->pool[i] = NULL;
		}
	}
}


/* sometimes alloc/free could use kmalloc with SLAB_DMA, for
 * better sharing and to leverage mm/slab.c intelligence.
 */

void *hcd_buffer_alloc (
	struct usb_bus 		*bus,
	size_t			size,
	int			mem_flags,
	dma_addr_t		*dma
)
{
	struct usb_hcd		*hcd = bus->hcpriv;
	int 			i;

	/* some USB hosts just use PIO */
	if (!bus->controller->dma_mask) {
		*dma = ~(dma_addr_t) 0;
		return kmalloc (size, mem_flags);
	}

	for (i = 0; i < HCD_BUFFER_POOLS; i++) {
		if (size <= pool_max [i])
			return dma_pool_alloc (hcd->pool [i], mem_flags, dma);
	}
	return dma_alloc_coherent (hcd->self.controller, size, dma, 0);
}

void hcd_buffer_free (
	struct usb_bus 		*bus,
	size_t			size,
	void 			*addr,
	dma_addr_t		dma
)
{
	struct usb_hcd		*hcd = bus->hcpriv;
	int 			i;

	if (!addr)
		return;

	if (!bus->controller->dma_mask) {
		kfree (addr);
		return;
	}

	for (i = 0; i < HCD_BUFFER_POOLS; i++) {
		if (size <= pool_max [i]) {
			dma_pool_free (hcd->pool [i], addr, dma);
			return;
		}
	}
	dma_free_coherent (hcd->self.controller, size, addr, dma);
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* DMA memory management for framework level HCD code (hc_driver)
	3	*
	4	* This implementation plugs in through generic "usb_bus" level methods,
	5	* and should work with all USB controllers, regardles of bus type.
	6	*/
	7
	8	#include <linux/config.h>
	9	#include <linux/module.h>
	10	#include <linux/kernel.h>
	11	#include <linux/slab.h>
	12	#include <linux/device.h>
	13	#include <linux/mm.h>
	14	#include <asm/io.h>
	15	#include <asm/scatterlist.h>
	16	#include <linux/dma-mapping.h>
	17	#include <linux/dmapool.h>
	18
	19
	20	#ifdef CONFIG_USB_DEBUG
	21	#define DEBUG
	22	#else
	23	#undef DEBUG
	24	#endif
	25
	26	#include <linux/usb.h>
	27	#include "hcd.h"
	28
	29
	30	/*
	31	* DMA-Coherent Buffers
	32	*/
	33
	34	/* FIXME tune these based on pool statistics ... */
	35	static const size_t pool_max [HCD_BUFFER_POOLS] = {
	36	/* platforms without dma-friendly caches might need to
	37	* prevent cacheline sharing...
	38	*/
	39	32,
	40	128,
	41	512,
	42	PAGE_SIZE / 2
	43	/* bigger --> allocate pages */
	44	};
	45
	46
	47	/* SETUP primitives */
	48
	49	/**
	50	* hcd_buffer_create - initialize buffer pools
	51	* @hcd: the bus whose buffer pools are to be initialized
	52	* Context: !in_interrupt()
	53	*
	54	* Call this as part of initializing a host controller that uses the dma
	55	* memory allocators. It initializes some pools of dma-coherent memory that
	56	* will be shared by all drivers using that controller, or returns a negative
	57	* errno value on error.
	58	*
	59	* Call hcd_buffer_destroy() to clean up after using those pools.
	60	*/
	61	int hcd_buffer_create (struct usb_hcd *hcd)
	62	{
	63	char name [16];
	64	int i, size;
65
66	for (i = 0; i < HCD_BUFFER_POOLS; i++) {
67	if (!(size = pool_max [i]))
68	continue;
69	snprintf (name, sizeof name, "buffer-%d", size);
70	hcd->pool [i] = dma_pool_create (name, hcd->self.controller,
71	size, size, 0);
72	if (!hcd->pool [i]) {
73	hcd_buffer_destroy (hcd);
74	return -ENOMEM;
75	}
76	}
77	return 0;
78	}
79
80
81	/**
82	* hcd_buffer_destroy - deallocate buffer pools
83	* @hcd: the bus whose buffer pools are to be destroyed
84	* Context: !in_interrupt()
85	*
86	* This frees the buffer pools created by hcd_buffer_create().
87	*/
88	void hcd_buffer_destroy (struct usb_hcd *hcd)
89	{
90	int i;
91
92	for (i = 0; i < HCD_BUFFER_POOLS; i++) {
93	struct dma_pool *pool = hcd->pool [i];
94	if (pool) {
95	dma_pool_destroy (pool);
96	hcd->pool[i] = NULL;
97	}
98	}
99	}
100
101
102	/* sometimes alloc/free could use kmalloc with SLAB_DMA, for
103	* better sharing and to leverage mm/slab.c intelligence.
104	*/
105
106	void *hcd_buffer_alloc (
107	struct usb_bus *bus,
108	size_t size,
109	int mem_flags,
110	dma_addr_t *dma
111	)
112	{
113	struct usb_hcd *hcd = bus->hcpriv;
114	int i;
115
116	/* some USB hosts just use PIO */
117	if (!bus->controller->dma_mask) {
118	*dma = ~(dma_addr_t) 0;
119	return kmalloc (size, mem_flags);
120	}
121
122	for (i = 0; i < HCD_BUFFER_POOLS; i++) {
123	if (size <= pool_max [i])
124	return dma_pool_alloc (hcd->pool [i], mem_flags, dma);
125	}
126	return dma_alloc_coherent (hcd->self.controller, size, dma, 0);
127	}
128
129	void hcd_buffer_free (
130	struct usb_bus *bus,
131	size_t size,
132	void *addr,
133	dma_addr_t dma
134	)
135	{
136	struct usb_hcd *hcd = bus->hcpriv;
137	int i;
138
139	if (!addr)
140	return;
141
142	if (!bus->controller->dma_mask) {
143	kfree (addr);
144	return;
145	}
146
147	for (i = 0; i < HCD_BUFFER_POOLS; i++) {
148	if (size <= pool_max [i]) {
149	dma_pool_free (hcd->pool [i], addr, dma);
150	return;
151	}
152	}
153	dma_free_coherent (hcd->self.controller, size, addr, dma);
154	}