ALSA: ctxfi - fix PTP address initialization

After hours of debugging, I finally found the reason why some source
and runtime combination does not work. The PTP (page table pages)
address must be aligned. I am not sure how much, but alignment to
PAGE_SIZE is sufficient. Also, use ALSA's page allocation routines
to ensure proper virtual -> physical address translation.

Cc: <[e-mail]>
Signed-off-by: Jaroslav Kysela <[e-mail]>

sound/pci/ctxfi/ctatc.c

···
 
 static unsigned long atc_get_ptp_phys(struct ct_atc *atc, int index)
 {
-	struct ct_vm *vm;
-	void *kvirt_addr;
-	unsigned long phys_addr;
-
-	vm = atc->vm;
-	kvirt_addr = vm->get_ptp_virt(vm, index);
-	if (kvirt_addr == NULL)
-		phys_addr = (~0UL);
-	else
-		phys_addr = virt_to_phys(kvirt_addr);
-
-	return phys_addr;
+	return atc->vm->get_ptp_phys(atc->vm, index);
 }
 
 static unsigned int convert_format(snd_pcm_format_t snd_format)
···
 	}
 
 	/* Set up device virtual memory management object */
-	err = ct_vm_create(&atc->vm);
+	err = ct_vm_create(&atc->vm, pci);
 	if (err < 0)
 		goto error1;
 

sound/pci/ctxfi/ctvmem.c

···
 		return NULL;
 	}
 
-	ptp = vm->ptp[0];
+	ptp = (unsigned long *)vm->ptp[0].area;
 	pte_start = (block->addr >> CT_PAGE_SHIFT);
 	pages = block->size >> CT_PAGE_SHIFT;
 	for (i = 0; i < pages; i++) {
···
 }
 
 /* *
- * return the host (kmalloced) addr of the @index-th device
- * page talbe page on success, or NULL on failure.
- * The first returned NULL indicates the termination.
+ * return the host physical addr of the @index-th device
+ * page table page on success, or ~0UL on failure.
+ * The first returned ~0UL indicates the termination.
  * */
-static void *
-ct_get_ptp_virt(struct ct_vm *vm, int index)
+static dma_addr_t
+ct_get_ptp_phys(struct ct_vm *vm, int index)
 {
-	void *addr;
+	dma_addr_t addr;
 
-	addr = (index >= CT_PTP_NUM) ? NULL : vm->ptp[index];
+	addr = (index >= CT_PTP_NUM) ? ~0UL : vm->ptp[index].addr;
 
 	return addr;
 }
 
-int ct_vm_create(struct ct_vm **rvm)
+int ct_vm_create(struct ct_vm **rvm, struct pci_dev *pci)
 {
 	struct ct_vm *vm;
 	struct ct_vm_block *block;
-	int i;
+	int i, err = 0;
 
 	*rvm = NULL;
 
···
 
 	/* Allocate page table pages */
 	for (i = 0; i < CT_PTP_NUM; i++) {
-		vm->ptp[i] = kmalloc(PAGE_SIZE, GFP_KERNEL);
-		if (!vm->ptp[i])
+		err = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV,
+					  snd_dma_pci_data(pci),
+					  PAGE_SIZE, &vm->ptp[i]);
+		if (err < 0)
 			break;
 	}
-	if (!i) {
+	if (err < 0) {
 		/* no page table pages are allocated */
-		kfree(vm);
+		ct_vm_destroy(vm);
 		return -ENOMEM;
 	}
 	vm->size = CT_ADDRS_PER_PAGE * i;
-	/* Initialise remaining ptps */
-	for (; i < CT_PTP_NUM; i++)
-		vm->ptp[i] = NULL;
-
 	vm->map = ct_vm_map;
 	vm->unmap = ct_vm_unmap;
-	vm->get_ptp_virt = ct_get_ptp_virt;
+	vm->get_ptp_phys = ct_get_ptp_phys;
 	INIT_LIST_HEAD(&vm->unused);
 	INIT_LIST_HEAD(&vm->used);
 	block = kzalloc(sizeof(*block), GFP_KERNEL);
···
 
 	/* free allocated page table pages */
 	for (i = 0; i < CT_PTP_NUM; i++)
-		kfree(vm->ptp[i]);
+		snd_dma_free_pages(&vm->ptp[i]);
 
 	vm->size = 0;
 

sound/pci/ctxfi/ctvmem.h

···
 
 #include <linux/mutex.h>
 #include <linux/list.h>
+#include <linux/pci.h>
+#include <sound/memalloc.h>
 
 /* The chip can handle the page table of 4k pages
  * (emu20k1 can handle even 8k pages, but we don't use it right now)
···
 
 /* Virtual memory management object for card device */
 struct ct_vm {
-	void *ptp[CT_PTP_NUM];		/* Device page table pages */
+	struct snd_dma_buffer ptp[CT_PTP_NUM];	/* Device page table pages */
 	unsigned int size;		/* Available addr space in bytes */
 	struct list_head unused;	/* List of unused blocks */
 	struct list_head used;		/* List of used blocks */
···
 				   int size);
 	/* Unmap device logical addr area. */
 	void (*unmap)(struct ct_vm *, struct ct_vm_block *block);
-	void *(*get_ptp_virt)(struct ct_vm *vm, int index);
+	dma_addr_t (*get_ptp_phys)(struct ct_vm *vm, int index);
 };
 
-int ct_vm_create(struct ct_vm **rvm);
+int ct_vm_create(struct ct_vm **rvm, struct pci_dev *pci);
 void ct_vm_destroy(struct ct_vm *vm);
 
 #endif /* CTVMEM_H */