1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-or-later
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * Broadcom BCM63xx SPI controller support
4*4882a593Smuzhiyun *
5*4882a593Smuzhiyun * Copyright (C) 2009-2012 Florian Fainelli <florian@openwrt.org>
6*4882a593Smuzhiyun * Copyright (C) 2010 Tanguy Bouzeloc <tanguy.bouzeloc@efixo.com>
7*4882a593Smuzhiyun */
8*4882a593Smuzhiyun
9*4882a593Smuzhiyun #include <linux/kernel.h>
10*4882a593Smuzhiyun #include <linux/clk.h>
11*4882a593Smuzhiyun #include <linux/io.h>
12*4882a593Smuzhiyun #include <linux/module.h>
13*4882a593Smuzhiyun #include <linux/platform_device.h>
14*4882a593Smuzhiyun #include <linux/delay.h>
15*4882a593Smuzhiyun #include <linux/interrupt.h>
16*4882a593Smuzhiyun #include <linux/spi/spi.h>
17*4882a593Smuzhiyun #include <linux/completion.h>
18*4882a593Smuzhiyun #include <linux/err.h>
19*4882a593Smuzhiyun #include <linux/pm_runtime.h>
20*4882a593Smuzhiyun #include <linux/of.h>
21*4882a593Smuzhiyun #include <linux/reset.h>
22*4882a593Smuzhiyun
23*4882a593Smuzhiyun /* BCM 6338/6348 SPI core */
24*4882a593Smuzhiyun #define SPI_6348_RSET_SIZE 64
25*4882a593Smuzhiyun #define SPI_6348_CMD 0x00 /* 16-bits register */
26*4882a593Smuzhiyun #define SPI_6348_INT_STATUS 0x02
27*4882a593Smuzhiyun #define SPI_6348_INT_MASK_ST 0x03
28*4882a593Smuzhiyun #define SPI_6348_INT_MASK 0x04
29*4882a593Smuzhiyun #define SPI_6348_ST 0x05
30*4882a593Smuzhiyun #define SPI_6348_CLK_CFG 0x06
31*4882a593Smuzhiyun #define SPI_6348_FILL_BYTE 0x07
32*4882a593Smuzhiyun #define SPI_6348_MSG_TAIL 0x09
33*4882a593Smuzhiyun #define SPI_6348_RX_TAIL 0x0b
34*4882a593Smuzhiyun #define SPI_6348_MSG_CTL 0x40 /* 8-bits register */
35*4882a593Smuzhiyun #define SPI_6348_MSG_CTL_WIDTH 8
36*4882a593Smuzhiyun #define SPI_6348_MSG_DATA 0x41
37*4882a593Smuzhiyun #define SPI_6348_MSG_DATA_SIZE 0x3f
38*4882a593Smuzhiyun #define SPI_6348_RX_DATA 0x80
39*4882a593Smuzhiyun #define SPI_6348_RX_DATA_SIZE 0x3f
40*4882a593Smuzhiyun
41*4882a593Smuzhiyun /* BCM 3368/6358/6262/6368 SPI core */
42*4882a593Smuzhiyun #define SPI_6358_RSET_SIZE 1804
43*4882a593Smuzhiyun #define SPI_6358_MSG_CTL 0x00 /* 16-bits register */
44*4882a593Smuzhiyun #define SPI_6358_MSG_CTL_WIDTH 16
45*4882a593Smuzhiyun #define SPI_6358_MSG_DATA 0x02
46*4882a593Smuzhiyun #define SPI_6358_MSG_DATA_SIZE 0x21e
47*4882a593Smuzhiyun #define SPI_6358_RX_DATA 0x400
48*4882a593Smuzhiyun #define SPI_6358_RX_DATA_SIZE 0x220
49*4882a593Smuzhiyun #define SPI_6358_CMD 0x700 /* 16-bits register */
50*4882a593Smuzhiyun #define SPI_6358_INT_STATUS 0x702
51*4882a593Smuzhiyun #define SPI_6358_INT_MASK_ST 0x703
52*4882a593Smuzhiyun #define SPI_6358_INT_MASK 0x704
53*4882a593Smuzhiyun #define SPI_6358_ST 0x705
54*4882a593Smuzhiyun #define SPI_6358_CLK_CFG 0x706
55*4882a593Smuzhiyun #define SPI_6358_FILL_BYTE 0x707
56*4882a593Smuzhiyun #define SPI_6358_MSG_TAIL 0x709
57*4882a593Smuzhiyun #define SPI_6358_RX_TAIL 0x70B
58*4882a593Smuzhiyun
59*4882a593Smuzhiyun /* Shared SPI definitions */
60*4882a593Smuzhiyun
61*4882a593Smuzhiyun /* Message configuration */
62*4882a593Smuzhiyun #define SPI_FD_RW 0x00
63*4882a593Smuzhiyun #define SPI_HD_W 0x01
64*4882a593Smuzhiyun #define SPI_HD_R 0x02
65*4882a593Smuzhiyun #define SPI_BYTE_CNT_SHIFT 0
66*4882a593Smuzhiyun #define SPI_6348_MSG_TYPE_SHIFT 6
67*4882a593Smuzhiyun #define SPI_6358_MSG_TYPE_SHIFT 14
68*4882a593Smuzhiyun
69*4882a593Smuzhiyun /* Command */
70*4882a593Smuzhiyun #define SPI_CMD_NOOP 0x00
71*4882a593Smuzhiyun #define SPI_CMD_SOFT_RESET 0x01
72*4882a593Smuzhiyun #define SPI_CMD_HARD_RESET 0x02
73*4882a593Smuzhiyun #define SPI_CMD_START_IMMEDIATE 0x03
74*4882a593Smuzhiyun #define SPI_CMD_COMMAND_SHIFT 0
75*4882a593Smuzhiyun #define SPI_CMD_COMMAND_MASK 0x000f
76*4882a593Smuzhiyun #define SPI_CMD_DEVICE_ID_SHIFT 4
77*4882a593Smuzhiyun #define SPI_CMD_PREPEND_BYTE_CNT_SHIFT 8
78*4882a593Smuzhiyun #define SPI_CMD_ONE_BYTE_SHIFT 11
79*4882a593Smuzhiyun #define SPI_CMD_ONE_WIRE_SHIFT 12
80*4882a593Smuzhiyun #define SPI_DEV_ID_0 0
81*4882a593Smuzhiyun #define SPI_DEV_ID_1 1
82*4882a593Smuzhiyun #define SPI_DEV_ID_2 2
83*4882a593Smuzhiyun #define SPI_DEV_ID_3 3
84*4882a593Smuzhiyun
85*4882a593Smuzhiyun /* Interrupt mask */
86*4882a593Smuzhiyun #define SPI_INTR_CMD_DONE 0x01
87*4882a593Smuzhiyun #define SPI_INTR_RX_OVERFLOW 0x02
88*4882a593Smuzhiyun #define SPI_INTR_TX_UNDERFLOW 0x04
89*4882a593Smuzhiyun #define SPI_INTR_TX_OVERFLOW 0x08
90*4882a593Smuzhiyun #define SPI_INTR_RX_UNDERFLOW 0x10
91*4882a593Smuzhiyun #define SPI_INTR_CLEAR_ALL 0x1f
92*4882a593Smuzhiyun
93*4882a593Smuzhiyun /* Status */
94*4882a593Smuzhiyun #define SPI_RX_EMPTY 0x02
95*4882a593Smuzhiyun #define SPI_CMD_BUSY 0x04
96*4882a593Smuzhiyun #define SPI_SERIAL_BUSY 0x08
97*4882a593Smuzhiyun
98*4882a593Smuzhiyun /* Clock configuration */
99*4882a593Smuzhiyun #define SPI_CLK_20MHZ 0x00
100*4882a593Smuzhiyun #define SPI_CLK_0_391MHZ 0x01
101*4882a593Smuzhiyun #define SPI_CLK_0_781MHZ 0x02 /* default */
102*4882a593Smuzhiyun #define SPI_CLK_1_563MHZ 0x03
103*4882a593Smuzhiyun #define SPI_CLK_3_125MHZ 0x04
104*4882a593Smuzhiyun #define SPI_CLK_6_250MHZ 0x05
105*4882a593Smuzhiyun #define SPI_CLK_12_50MHZ 0x06
106*4882a593Smuzhiyun #define SPI_CLK_MASK 0x07
107*4882a593Smuzhiyun #define SPI_SSOFFTIME_MASK 0x38
108*4882a593Smuzhiyun #define SPI_SSOFFTIME_SHIFT 3
109*4882a593Smuzhiyun #define SPI_BYTE_SWAP 0x80
110*4882a593Smuzhiyun
111*4882a593Smuzhiyun enum bcm63xx_regs_spi {
112*4882a593Smuzhiyun SPI_CMD,
113*4882a593Smuzhiyun SPI_INT_STATUS,
114*4882a593Smuzhiyun SPI_INT_MASK_ST,
115*4882a593Smuzhiyun SPI_INT_MASK,
116*4882a593Smuzhiyun SPI_ST,
117*4882a593Smuzhiyun SPI_CLK_CFG,
118*4882a593Smuzhiyun SPI_FILL_BYTE,
119*4882a593Smuzhiyun SPI_MSG_TAIL,
120*4882a593Smuzhiyun SPI_RX_TAIL,
121*4882a593Smuzhiyun SPI_MSG_CTL,
122*4882a593Smuzhiyun SPI_MSG_DATA,
123*4882a593Smuzhiyun SPI_RX_DATA,
124*4882a593Smuzhiyun SPI_MSG_TYPE_SHIFT,
125*4882a593Smuzhiyun SPI_MSG_CTL_WIDTH,
126*4882a593Smuzhiyun SPI_MSG_DATA_SIZE,
127*4882a593Smuzhiyun };
128*4882a593Smuzhiyun
129*4882a593Smuzhiyun #define BCM63XX_SPI_MAX_PREPEND 15
130*4882a593Smuzhiyun
131*4882a593Smuzhiyun #define BCM63XX_SPI_MAX_CS 8
132*4882a593Smuzhiyun #define BCM63XX_SPI_BUS_NUM 0
133*4882a593Smuzhiyun
134*4882a593Smuzhiyun struct bcm63xx_spi {
135*4882a593Smuzhiyun struct completion done;
136*4882a593Smuzhiyun
137*4882a593Smuzhiyun void __iomem *regs;
138*4882a593Smuzhiyun int irq;
139*4882a593Smuzhiyun
140*4882a593Smuzhiyun /* Platform data */
141*4882a593Smuzhiyun const unsigned long *reg_offsets;
142*4882a593Smuzhiyun unsigned int fifo_size;
143*4882a593Smuzhiyun unsigned int msg_type_shift;
144*4882a593Smuzhiyun unsigned int msg_ctl_width;
145*4882a593Smuzhiyun
146*4882a593Smuzhiyun /* data iomem */
147*4882a593Smuzhiyun u8 __iomem *tx_io;
148*4882a593Smuzhiyun const u8 __iomem *rx_io;
149*4882a593Smuzhiyun
150*4882a593Smuzhiyun struct clk *clk;
151*4882a593Smuzhiyun struct platform_device *pdev;
152*4882a593Smuzhiyun };
153*4882a593Smuzhiyun
bcm_spi_readb(struct bcm63xx_spi * bs,unsigned int offset)154*4882a593Smuzhiyun static inline u8 bcm_spi_readb(struct bcm63xx_spi *bs,
155*4882a593Smuzhiyun unsigned int offset)
156*4882a593Smuzhiyun {
157*4882a593Smuzhiyun return readb(bs->regs + bs->reg_offsets[offset]);
158*4882a593Smuzhiyun }
159*4882a593Smuzhiyun
bcm_spi_readw(struct bcm63xx_spi * bs,unsigned int offset)160*4882a593Smuzhiyun static inline u16 bcm_spi_readw(struct bcm63xx_spi *bs,
161*4882a593Smuzhiyun unsigned int offset)
162*4882a593Smuzhiyun {
163*4882a593Smuzhiyun #ifdef CONFIG_CPU_BIG_ENDIAN
164*4882a593Smuzhiyun return ioread16be(bs->regs + bs->reg_offsets[offset]);
165*4882a593Smuzhiyun #else
166*4882a593Smuzhiyun return readw(bs->regs + bs->reg_offsets[offset]);
167*4882a593Smuzhiyun #endif
168*4882a593Smuzhiyun }
169*4882a593Smuzhiyun
bcm_spi_writeb(struct bcm63xx_spi * bs,u8 value,unsigned int offset)170*4882a593Smuzhiyun static inline void bcm_spi_writeb(struct bcm63xx_spi *bs,
171*4882a593Smuzhiyun u8 value, unsigned int offset)
172*4882a593Smuzhiyun {
173*4882a593Smuzhiyun writeb(value, bs->regs + bs->reg_offsets[offset]);
174*4882a593Smuzhiyun }
175*4882a593Smuzhiyun
bcm_spi_writew(struct bcm63xx_spi * bs,u16 value,unsigned int offset)176*4882a593Smuzhiyun static inline void bcm_spi_writew(struct bcm63xx_spi *bs,
177*4882a593Smuzhiyun u16 value, unsigned int offset)
178*4882a593Smuzhiyun {
179*4882a593Smuzhiyun #ifdef CONFIG_CPU_BIG_ENDIAN
180*4882a593Smuzhiyun iowrite16be(value, bs->regs + bs->reg_offsets[offset]);
181*4882a593Smuzhiyun #else
182*4882a593Smuzhiyun writew(value, bs->regs + bs->reg_offsets[offset]);
183*4882a593Smuzhiyun #endif
184*4882a593Smuzhiyun }
185*4882a593Smuzhiyun
186*4882a593Smuzhiyun static const unsigned int bcm63xx_spi_freq_table[SPI_CLK_MASK][2] = {
187*4882a593Smuzhiyun { 20000000, SPI_CLK_20MHZ },
188*4882a593Smuzhiyun { 12500000, SPI_CLK_12_50MHZ },
189*4882a593Smuzhiyun { 6250000, SPI_CLK_6_250MHZ },
190*4882a593Smuzhiyun { 3125000, SPI_CLK_3_125MHZ },
191*4882a593Smuzhiyun { 1563000, SPI_CLK_1_563MHZ },
192*4882a593Smuzhiyun { 781000, SPI_CLK_0_781MHZ },
193*4882a593Smuzhiyun { 391000, SPI_CLK_0_391MHZ }
194*4882a593Smuzhiyun };
195*4882a593Smuzhiyun
bcm63xx_spi_setup_transfer(struct spi_device * spi,struct spi_transfer * t)196*4882a593Smuzhiyun static void bcm63xx_spi_setup_transfer(struct spi_device *spi,
197*4882a593Smuzhiyun struct spi_transfer *t)
198*4882a593Smuzhiyun {
199*4882a593Smuzhiyun struct bcm63xx_spi *bs = spi_master_get_devdata(spi->master);
200*4882a593Smuzhiyun u8 clk_cfg, reg;
201*4882a593Smuzhiyun int i;
202*4882a593Smuzhiyun
203*4882a593Smuzhiyun /* Default to lowest clock configuration */
204*4882a593Smuzhiyun clk_cfg = SPI_CLK_0_391MHZ;
205*4882a593Smuzhiyun
206*4882a593Smuzhiyun /* Find the closest clock configuration */
207*4882a593Smuzhiyun for (i = 0; i < SPI_CLK_MASK; i++) {
208*4882a593Smuzhiyun if (t->speed_hz >= bcm63xx_spi_freq_table[i][0]) {
209*4882a593Smuzhiyun clk_cfg = bcm63xx_spi_freq_table[i][1];
210*4882a593Smuzhiyun break;
211*4882a593Smuzhiyun }
212*4882a593Smuzhiyun }
213*4882a593Smuzhiyun
214*4882a593Smuzhiyun /* clear existing clock configuration bits of the register */
215*4882a593Smuzhiyun reg = bcm_spi_readb(bs, SPI_CLK_CFG);
216*4882a593Smuzhiyun reg &= ~SPI_CLK_MASK;
217*4882a593Smuzhiyun reg |= clk_cfg;
218*4882a593Smuzhiyun
219*4882a593Smuzhiyun bcm_spi_writeb(bs, reg, SPI_CLK_CFG);
220*4882a593Smuzhiyun dev_dbg(&spi->dev, "Setting clock register to %02x (hz %d)\n",
221*4882a593Smuzhiyun clk_cfg, t->speed_hz);
222*4882a593Smuzhiyun }
223*4882a593Smuzhiyun
224*4882a593Smuzhiyun /* the spi->mode bits understood by this driver: */
225*4882a593Smuzhiyun #define MODEBITS (SPI_CPOL | SPI_CPHA)
226*4882a593Smuzhiyun
bcm63xx_txrx_bufs(struct spi_device * spi,struct spi_transfer * first,unsigned int num_transfers)227*4882a593Smuzhiyun static int bcm63xx_txrx_bufs(struct spi_device *spi, struct spi_transfer *first,
228*4882a593Smuzhiyun unsigned int num_transfers)
229*4882a593Smuzhiyun {
230*4882a593Smuzhiyun struct bcm63xx_spi *bs = spi_master_get_devdata(spi->master);
231*4882a593Smuzhiyun u16 msg_ctl;
232*4882a593Smuzhiyun u16 cmd;
233*4882a593Smuzhiyun unsigned int i, timeout = 0, prepend_len = 0, len = 0;
234*4882a593Smuzhiyun struct spi_transfer *t = first;
235*4882a593Smuzhiyun bool do_rx = false;
236*4882a593Smuzhiyun bool do_tx = false;
237*4882a593Smuzhiyun
238*4882a593Smuzhiyun /* Disable the CMD_DONE interrupt */
239*4882a593Smuzhiyun bcm_spi_writeb(bs, 0, SPI_INT_MASK);
240*4882a593Smuzhiyun
241*4882a593Smuzhiyun dev_dbg(&spi->dev, "txrx: tx %p, rx %p, len %d\n",
242*4882a593Smuzhiyun t->tx_buf, t->rx_buf, t->len);
243*4882a593Smuzhiyun
244*4882a593Smuzhiyun if (num_transfers > 1 && t->tx_buf && t->len <= BCM63XX_SPI_MAX_PREPEND)
245*4882a593Smuzhiyun prepend_len = t->len;
246*4882a593Smuzhiyun
247*4882a593Smuzhiyun /* prepare the buffer */
248*4882a593Smuzhiyun for (i = 0; i < num_transfers; i++) {
249*4882a593Smuzhiyun if (t->tx_buf) {
250*4882a593Smuzhiyun do_tx = true;
251*4882a593Smuzhiyun memcpy_toio(bs->tx_io + len, t->tx_buf, t->len);
252*4882a593Smuzhiyun
253*4882a593Smuzhiyun /* don't prepend more than one tx */
254*4882a593Smuzhiyun if (t != first)
255*4882a593Smuzhiyun prepend_len = 0;
256*4882a593Smuzhiyun }
257*4882a593Smuzhiyun
258*4882a593Smuzhiyun if (t->rx_buf) {
259*4882a593Smuzhiyun do_rx = true;
260*4882a593Smuzhiyun /* prepend is half-duplex write only */
261*4882a593Smuzhiyun if (t == first)
262*4882a593Smuzhiyun prepend_len = 0;
263*4882a593Smuzhiyun }
264*4882a593Smuzhiyun
265*4882a593Smuzhiyun len += t->len;
266*4882a593Smuzhiyun
267*4882a593Smuzhiyun t = list_entry(t->transfer_list.next, struct spi_transfer,
268*4882a593Smuzhiyun transfer_list);
269*4882a593Smuzhiyun }
270*4882a593Smuzhiyun
271*4882a593Smuzhiyun reinit_completion(&bs->done);
272*4882a593Smuzhiyun
273*4882a593Smuzhiyun /* Fill in the Message control register */
274*4882a593Smuzhiyun msg_ctl = (len << SPI_BYTE_CNT_SHIFT);
275*4882a593Smuzhiyun
276*4882a593Smuzhiyun if (do_rx && do_tx && prepend_len == 0)
277*4882a593Smuzhiyun msg_ctl |= (SPI_FD_RW << bs->msg_type_shift);
278*4882a593Smuzhiyun else if (do_rx)
279*4882a593Smuzhiyun msg_ctl |= (SPI_HD_R << bs->msg_type_shift);
280*4882a593Smuzhiyun else if (do_tx)
281*4882a593Smuzhiyun msg_ctl |= (SPI_HD_W << bs->msg_type_shift);
282*4882a593Smuzhiyun
283*4882a593Smuzhiyun switch (bs->msg_ctl_width) {
284*4882a593Smuzhiyun case 8:
285*4882a593Smuzhiyun bcm_spi_writeb(bs, msg_ctl, SPI_MSG_CTL);
286*4882a593Smuzhiyun break;
287*4882a593Smuzhiyun case 16:
288*4882a593Smuzhiyun bcm_spi_writew(bs, msg_ctl, SPI_MSG_CTL);
289*4882a593Smuzhiyun break;
290*4882a593Smuzhiyun }
291*4882a593Smuzhiyun
292*4882a593Smuzhiyun /* Issue the transfer */
293*4882a593Smuzhiyun cmd = SPI_CMD_START_IMMEDIATE;
294*4882a593Smuzhiyun cmd |= (prepend_len << SPI_CMD_PREPEND_BYTE_CNT_SHIFT);
295*4882a593Smuzhiyun cmd |= (spi->chip_select << SPI_CMD_DEVICE_ID_SHIFT);
296*4882a593Smuzhiyun bcm_spi_writew(bs, cmd, SPI_CMD);
297*4882a593Smuzhiyun
298*4882a593Smuzhiyun /* Enable the CMD_DONE interrupt */
299*4882a593Smuzhiyun bcm_spi_writeb(bs, SPI_INTR_CMD_DONE, SPI_INT_MASK);
300*4882a593Smuzhiyun
301*4882a593Smuzhiyun timeout = wait_for_completion_timeout(&bs->done, HZ);
302*4882a593Smuzhiyun if (!timeout)
303*4882a593Smuzhiyun return -ETIMEDOUT;
304*4882a593Smuzhiyun
305*4882a593Smuzhiyun if (!do_rx)
306*4882a593Smuzhiyun return 0;
307*4882a593Smuzhiyun
308*4882a593Smuzhiyun len = 0;
309*4882a593Smuzhiyun t = first;
310*4882a593Smuzhiyun /* Read out all the data */
311*4882a593Smuzhiyun for (i = 0; i < num_transfers; i++) {
312*4882a593Smuzhiyun if (t->rx_buf)
313*4882a593Smuzhiyun memcpy_fromio(t->rx_buf, bs->rx_io + len, t->len);
314*4882a593Smuzhiyun
315*4882a593Smuzhiyun if (t != first || prepend_len == 0)
316*4882a593Smuzhiyun len += t->len;
317*4882a593Smuzhiyun
318*4882a593Smuzhiyun t = list_entry(t->transfer_list.next, struct spi_transfer,
319*4882a593Smuzhiyun transfer_list);
320*4882a593Smuzhiyun }
321*4882a593Smuzhiyun
322*4882a593Smuzhiyun return 0;
323*4882a593Smuzhiyun }
324*4882a593Smuzhiyun
bcm63xx_spi_transfer_one(struct spi_master * master,struct spi_message * m)325*4882a593Smuzhiyun static int bcm63xx_spi_transfer_one(struct spi_master *master,
326*4882a593Smuzhiyun struct spi_message *m)
327*4882a593Smuzhiyun {
328*4882a593Smuzhiyun struct bcm63xx_spi *bs = spi_master_get_devdata(master);
329*4882a593Smuzhiyun struct spi_transfer *t, *first = NULL;
330*4882a593Smuzhiyun struct spi_device *spi = m->spi;
331*4882a593Smuzhiyun int status = 0;
332*4882a593Smuzhiyun unsigned int n_transfers = 0, total_len = 0;
333*4882a593Smuzhiyun bool can_use_prepend = false;
334*4882a593Smuzhiyun
335*4882a593Smuzhiyun /*
336*4882a593Smuzhiyun * This SPI controller does not support keeping CS active after a
337*4882a593Smuzhiyun * transfer.
338*4882a593Smuzhiyun * Work around this by merging as many transfers we can into one big
339*4882a593Smuzhiyun * full-duplex transfers.
340*4882a593Smuzhiyun */
341*4882a593Smuzhiyun list_for_each_entry(t, &m->transfers, transfer_list) {
342*4882a593Smuzhiyun if (!first)
343*4882a593Smuzhiyun first = t;
344*4882a593Smuzhiyun
345*4882a593Smuzhiyun n_transfers++;
346*4882a593Smuzhiyun total_len += t->len;
347*4882a593Smuzhiyun
348*4882a593Smuzhiyun if (n_transfers == 2 && !first->rx_buf && !t->tx_buf &&
349*4882a593Smuzhiyun first->len <= BCM63XX_SPI_MAX_PREPEND)
350*4882a593Smuzhiyun can_use_prepend = true;
351*4882a593Smuzhiyun else if (can_use_prepend && t->tx_buf)
352*4882a593Smuzhiyun can_use_prepend = false;
353*4882a593Smuzhiyun
354*4882a593Smuzhiyun /* we can only transfer one fifo worth of data */
355*4882a593Smuzhiyun if ((can_use_prepend &&
356*4882a593Smuzhiyun total_len > (bs->fifo_size + BCM63XX_SPI_MAX_PREPEND)) ||
357*4882a593Smuzhiyun (!can_use_prepend && total_len > bs->fifo_size)) {
358*4882a593Smuzhiyun dev_err(&spi->dev, "unable to do transfers larger than FIFO size (%i > %i)\n",
359*4882a593Smuzhiyun total_len, bs->fifo_size);
360*4882a593Smuzhiyun status = -EINVAL;
361*4882a593Smuzhiyun goto exit;
362*4882a593Smuzhiyun }
363*4882a593Smuzhiyun
364*4882a593Smuzhiyun /* all combined transfers have to have the same speed */
365*4882a593Smuzhiyun if (t->speed_hz != first->speed_hz) {
366*4882a593Smuzhiyun dev_err(&spi->dev, "unable to change speed between transfers\n");
367*4882a593Smuzhiyun status = -EINVAL;
368*4882a593Smuzhiyun goto exit;
369*4882a593Smuzhiyun }
370*4882a593Smuzhiyun
371*4882a593Smuzhiyun /* CS will be deasserted directly after transfer */
372*4882a593Smuzhiyun if (t->delay_usecs || t->delay.value) {
373*4882a593Smuzhiyun dev_err(&spi->dev, "unable to keep CS asserted after transfer\n");
374*4882a593Smuzhiyun status = -EINVAL;
375*4882a593Smuzhiyun goto exit;
376*4882a593Smuzhiyun }
377*4882a593Smuzhiyun
378*4882a593Smuzhiyun if (t->cs_change ||
379*4882a593Smuzhiyun list_is_last(&t->transfer_list, &m->transfers)) {
380*4882a593Smuzhiyun /* configure adapter for a new transfer */
381*4882a593Smuzhiyun bcm63xx_spi_setup_transfer(spi, first);
382*4882a593Smuzhiyun
383*4882a593Smuzhiyun /* send the data */
384*4882a593Smuzhiyun status = bcm63xx_txrx_bufs(spi, first, n_transfers);
385*4882a593Smuzhiyun if (status)
386*4882a593Smuzhiyun goto exit;
387*4882a593Smuzhiyun
388*4882a593Smuzhiyun m->actual_length += total_len;
389*4882a593Smuzhiyun
390*4882a593Smuzhiyun first = NULL;
391*4882a593Smuzhiyun n_transfers = 0;
392*4882a593Smuzhiyun total_len = 0;
393*4882a593Smuzhiyun can_use_prepend = false;
394*4882a593Smuzhiyun }
395*4882a593Smuzhiyun }
396*4882a593Smuzhiyun exit:
397*4882a593Smuzhiyun m->status = status;
398*4882a593Smuzhiyun spi_finalize_current_message(master);
399*4882a593Smuzhiyun
400*4882a593Smuzhiyun return 0;
401*4882a593Smuzhiyun }
402*4882a593Smuzhiyun
403*4882a593Smuzhiyun /* This driver supports single master mode only. Hence
404*4882a593Smuzhiyun * CMD_DONE is the only interrupt we care about
405*4882a593Smuzhiyun */
bcm63xx_spi_interrupt(int irq,void * dev_id)406*4882a593Smuzhiyun static irqreturn_t bcm63xx_spi_interrupt(int irq, void *dev_id)
407*4882a593Smuzhiyun {
408*4882a593Smuzhiyun struct spi_master *master = (struct spi_master *)dev_id;
409*4882a593Smuzhiyun struct bcm63xx_spi *bs = spi_master_get_devdata(master);
410*4882a593Smuzhiyun u8 intr;
411*4882a593Smuzhiyun
412*4882a593Smuzhiyun /* Read interupts and clear them immediately */
413*4882a593Smuzhiyun intr = bcm_spi_readb(bs, SPI_INT_STATUS);
414*4882a593Smuzhiyun bcm_spi_writeb(bs, SPI_INTR_CLEAR_ALL, SPI_INT_STATUS);
415*4882a593Smuzhiyun bcm_spi_writeb(bs, 0, SPI_INT_MASK);
416*4882a593Smuzhiyun
417*4882a593Smuzhiyun /* A transfer completed */
418*4882a593Smuzhiyun if (intr & SPI_INTR_CMD_DONE)
419*4882a593Smuzhiyun complete(&bs->done);
420*4882a593Smuzhiyun
421*4882a593Smuzhiyun return IRQ_HANDLED;
422*4882a593Smuzhiyun }
423*4882a593Smuzhiyun
bcm63xx_spi_max_length(struct spi_device * spi)424*4882a593Smuzhiyun static size_t bcm63xx_spi_max_length(struct spi_device *spi)
425*4882a593Smuzhiyun {
426*4882a593Smuzhiyun struct bcm63xx_spi *bs = spi_master_get_devdata(spi->master);
427*4882a593Smuzhiyun
428*4882a593Smuzhiyun return bs->fifo_size;
429*4882a593Smuzhiyun }
430*4882a593Smuzhiyun
431*4882a593Smuzhiyun static const unsigned long bcm6348_spi_reg_offsets[] = {
432*4882a593Smuzhiyun [SPI_CMD] = SPI_6348_CMD,
433*4882a593Smuzhiyun [SPI_INT_STATUS] = SPI_6348_INT_STATUS,
434*4882a593Smuzhiyun [SPI_INT_MASK_ST] = SPI_6348_INT_MASK_ST,
435*4882a593Smuzhiyun [SPI_INT_MASK] = SPI_6348_INT_MASK,
436*4882a593Smuzhiyun [SPI_ST] = SPI_6348_ST,
437*4882a593Smuzhiyun [SPI_CLK_CFG] = SPI_6348_CLK_CFG,
438*4882a593Smuzhiyun [SPI_FILL_BYTE] = SPI_6348_FILL_BYTE,
439*4882a593Smuzhiyun [SPI_MSG_TAIL] = SPI_6348_MSG_TAIL,
440*4882a593Smuzhiyun [SPI_RX_TAIL] = SPI_6348_RX_TAIL,
441*4882a593Smuzhiyun [SPI_MSG_CTL] = SPI_6348_MSG_CTL,
442*4882a593Smuzhiyun [SPI_MSG_DATA] = SPI_6348_MSG_DATA,
443*4882a593Smuzhiyun [SPI_RX_DATA] = SPI_6348_RX_DATA,
444*4882a593Smuzhiyun [SPI_MSG_TYPE_SHIFT] = SPI_6348_MSG_TYPE_SHIFT,
445*4882a593Smuzhiyun [SPI_MSG_CTL_WIDTH] = SPI_6348_MSG_CTL_WIDTH,
446*4882a593Smuzhiyun [SPI_MSG_DATA_SIZE] = SPI_6348_MSG_DATA_SIZE,
447*4882a593Smuzhiyun };
448*4882a593Smuzhiyun
449*4882a593Smuzhiyun static const unsigned long bcm6358_spi_reg_offsets[] = {
450*4882a593Smuzhiyun [SPI_CMD] = SPI_6358_CMD,
451*4882a593Smuzhiyun [SPI_INT_STATUS] = SPI_6358_INT_STATUS,
452*4882a593Smuzhiyun [SPI_INT_MASK_ST] = SPI_6358_INT_MASK_ST,
453*4882a593Smuzhiyun [SPI_INT_MASK] = SPI_6358_INT_MASK,
454*4882a593Smuzhiyun [SPI_ST] = SPI_6358_ST,
455*4882a593Smuzhiyun [SPI_CLK_CFG] = SPI_6358_CLK_CFG,
456*4882a593Smuzhiyun [SPI_FILL_BYTE] = SPI_6358_FILL_BYTE,
457*4882a593Smuzhiyun [SPI_MSG_TAIL] = SPI_6358_MSG_TAIL,
458*4882a593Smuzhiyun [SPI_RX_TAIL] = SPI_6358_RX_TAIL,
459*4882a593Smuzhiyun [SPI_MSG_CTL] = SPI_6358_MSG_CTL,
460*4882a593Smuzhiyun [SPI_MSG_DATA] = SPI_6358_MSG_DATA,
461*4882a593Smuzhiyun [SPI_RX_DATA] = SPI_6358_RX_DATA,
462*4882a593Smuzhiyun [SPI_MSG_TYPE_SHIFT] = SPI_6358_MSG_TYPE_SHIFT,
463*4882a593Smuzhiyun [SPI_MSG_CTL_WIDTH] = SPI_6358_MSG_CTL_WIDTH,
464*4882a593Smuzhiyun [SPI_MSG_DATA_SIZE] = SPI_6358_MSG_DATA_SIZE,
465*4882a593Smuzhiyun };
466*4882a593Smuzhiyun
467*4882a593Smuzhiyun static const struct platform_device_id bcm63xx_spi_dev_match[] = {
468*4882a593Smuzhiyun {
469*4882a593Smuzhiyun .name = "bcm6348-spi",
470*4882a593Smuzhiyun .driver_data = (unsigned long)bcm6348_spi_reg_offsets,
471*4882a593Smuzhiyun },
472*4882a593Smuzhiyun {
473*4882a593Smuzhiyun .name = "bcm6358-spi",
474*4882a593Smuzhiyun .driver_data = (unsigned long)bcm6358_spi_reg_offsets,
475*4882a593Smuzhiyun },
476*4882a593Smuzhiyun {
477*4882a593Smuzhiyun },
478*4882a593Smuzhiyun };
479*4882a593Smuzhiyun
480*4882a593Smuzhiyun static const struct of_device_id bcm63xx_spi_of_match[] = {
481*4882a593Smuzhiyun { .compatible = "brcm,bcm6348-spi", .data = &bcm6348_spi_reg_offsets },
482*4882a593Smuzhiyun { .compatible = "brcm,bcm6358-spi", .data = &bcm6358_spi_reg_offsets },
483*4882a593Smuzhiyun { },
484*4882a593Smuzhiyun };
485*4882a593Smuzhiyun
bcm63xx_spi_probe(struct platform_device * pdev)486*4882a593Smuzhiyun static int bcm63xx_spi_probe(struct platform_device *pdev)
487*4882a593Smuzhiyun {
488*4882a593Smuzhiyun struct resource *r;
489*4882a593Smuzhiyun const unsigned long *bcm63xx_spireg;
490*4882a593Smuzhiyun struct device *dev = &pdev->dev;
491*4882a593Smuzhiyun int irq, bus_num;
492*4882a593Smuzhiyun struct spi_master *master;
493*4882a593Smuzhiyun struct clk *clk;
494*4882a593Smuzhiyun struct bcm63xx_spi *bs;
495*4882a593Smuzhiyun int ret;
496*4882a593Smuzhiyun u32 num_cs = BCM63XX_SPI_MAX_CS;
497*4882a593Smuzhiyun struct reset_control *reset;
498*4882a593Smuzhiyun
499*4882a593Smuzhiyun if (dev->of_node) {
500*4882a593Smuzhiyun const struct of_device_id *match;
501*4882a593Smuzhiyun
502*4882a593Smuzhiyun match = of_match_node(bcm63xx_spi_of_match, dev->of_node);
503*4882a593Smuzhiyun if (!match)
504*4882a593Smuzhiyun return -EINVAL;
505*4882a593Smuzhiyun bcm63xx_spireg = match->data;
506*4882a593Smuzhiyun
507*4882a593Smuzhiyun of_property_read_u32(dev->of_node, "num-cs", &num_cs);
508*4882a593Smuzhiyun if (num_cs > BCM63XX_SPI_MAX_CS) {
509*4882a593Smuzhiyun dev_warn(dev, "unsupported number of cs (%i), reducing to 8\n",
510*4882a593Smuzhiyun num_cs);
511*4882a593Smuzhiyun num_cs = BCM63XX_SPI_MAX_CS;
512*4882a593Smuzhiyun }
513*4882a593Smuzhiyun
514*4882a593Smuzhiyun bus_num = -1;
515*4882a593Smuzhiyun } else if (pdev->id_entry->driver_data) {
516*4882a593Smuzhiyun const struct platform_device_id *match = pdev->id_entry;
517*4882a593Smuzhiyun
518*4882a593Smuzhiyun bcm63xx_spireg = (const unsigned long *)match->driver_data;
519*4882a593Smuzhiyun bus_num = BCM63XX_SPI_BUS_NUM;
520*4882a593Smuzhiyun } else {
521*4882a593Smuzhiyun return -EINVAL;
522*4882a593Smuzhiyun }
523*4882a593Smuzhiyun
524*4882a593Smuzhiyun irq = platform_get_irq(pdev, 0);
525*4882a593Smuzhiyun if (irq < 0)
526*4882a593Smuzhiyun return irq;
527*4882a593Smuzhiyun
528*4882a593Smuzhiyun clk = devm_clk_get(dev, "spi");
529*4882a593Smuzhiyun if (IS_ERR(clk)) {
530*4882a593Smuzhiyun dev_err(dev, "no clock for device\n");
531*4882a593Smuzhiyun return PTR_ERR(clk);
532*4882a593Smuzhiyun }
533*4882a593Smuzhiyun
534*4882a593Smuzhiyun reset = devm_reset_control_get_optional_exclusive(dev, NULL);
535*4882a593Smuzhiyun if (IS_ERR(reset))
536*4882a593Smuzhiyun return PTR_ERR(reset);
537*4882a593Smuzhiyun
538*4882a593Smuzhiyun master = spi_alloc_master(dev, sizeof(*bs));
539*4882a593Smuzhiyun if (!master) {
540*4882a593Smuzhiyun dev_err(dev, "out of memory\n");
541*4882a593Smuzhiyun return -ENOMEM;
542*4882a593Smuzhiyun }
543*4882a593Smuzhiyun
544*4882a593Smuzhiyun bs = spi_master_get_devdata(master);
545*4882a593Smuzhiyun init_completion(&bs->done);
546*4882a593Smuzhiyun
547*4882a593Smuzhiyun platform_set_drvdata(pdev, master);
548*4882a593Smuzhiyun bs->pdev = pdev;
549*4882a593Smuzhiyun
550*4882a593Smuzhiyun r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
551*4882a593Smuzhiyun bs->regs = devm_ioremap_resource(&pdev->dev, r);
552*4882a593Smuzhiyun if (IS_ERR(bs->regs)) {
553*4882a593Smuzhiyun ret = PTR_ERR(bs->regs);
554*4882a593Smuzhiyun goto out_err;
555*4882a593Smuzhiyun }
556*4882a593Smuzhiyun
557*4882a593Smuzhiyun bs->irq = irq;
558*4882a593Smuzhiyun bs->clk = clk;
559*4882a593Smuzhiyun bs->reg_offsets = bcm63xx_spireg;
560*4882a593Smuzhiyun bs->fifo_size = bs->reg_offsets[SPI_MSG_DATA_SIZE];
561*4882a593Smuzhiyun
562*4882a593Smuzhiyun ret = devm_request_irq(&pdev->dev, irq, bcm63xx_spi_interrupt, 0,
563*4882a593Smuzhiyun pdev->name, master);
564*4882a593Smuzhiyun if (ret) {
565*4882a593Smuzhiyun dev_err(dev, "unable to request irq\n");
566*4882a593Smuzhiyun goto out_err;
567*4882a593Smuzhiyun }
568*4882a593Smuzhiyun
569*4882a593Smuzhiyun master->dev.of_node = dev->of_node;
570*4882a593Smuzhiyun master->bus_num = bus_num;
571*4882a593Smuzhiyun master->num_chipselect = num_cs;
572*4882a593Smuzhiyun master->transfer_one_message = bcm63xx_spi_transfer_one;
573*4882a593Smuzhiyun master->mode_bits = MODEBITS;
574*4882a593Smuzhiyun master->bits_per_word_mask = SPI_BPW_MASK(8);
575*4882a593Smuzhiyun master->max_transfer_size = bcm63xx_spi_max_length;
576*4882a593Smuzhiyun master->max_message_size = bcm63xx_spi_max_length;
577*4882a593Smuzhiyun master->auto_runtime_pm = true;
578*4882a593Smuzhiyun bs->msg_type_shift = bs->reg_offsets[SPI_MSG_TYPE_SHIFT];
579*4882a593Smuzhiyun bs->msg_ctl_width = bs->reg_offsets[SPI_MSG_CTL_WIDTH];
580*4882a593Smuzhiyun bs->tx_io = (u8 *)(bs->regs + bs->reg_offsets[SPI_MSG_DATA]);
581*4882a593Smuzhiyun bs->rx_io = (const u8 *)(bs->regs + bs->reg_offsets[SPI_RX_DATA]);
582*4882a593Smuzhiyun
583*4882a593Smuzhiyun /* Initialize hardware */
584*4882a593Smuzhiyun ret = clk_prepare_enable(bs->clk);
585*4882a593Smuzhiyun if (ret)
586*4882a593Smuzhiyun goto out_err;
587*4882a593Smuzhiyun
588*4882a593Smuzhiyun ret = reset_control_reset(reset);
589*4882a593Smuzhiyun if (ret) {
590*4882a593Smuzhiyun dev_err(dev, "unable to reset device: %d\n", ret);
591*4882a593Smuzhiyun goto out_clk_disable;
592*4882a593Smuzhiyun }
593*4882a593Smuzhiyun
594*4882a593Smuzhiyun bcm_spi_writeb(bs, SPI_INTR_CLEAR_ALL, SPI_INT_STATUS);
595*4882a593Smuzhiyun
596*4882a593Smuzhiyun /* register and we are done */
597*4882a593Smuzhiyun ret = devm_spi_register_master(dev, master);
598*4882a593Smuzhiyun if (ret) {
599*4882a593Smuzhiyun dev_err(dev, "spi register failed\n");
600*4882a593Smuzhiyun goto out_clk_disable;
601*4882a593Smuzhiyun }
602*4882a593Smuzhiyun
603*4882a593Smuzhiyun dev_info(dev, "at %pr (irq %d, FIFOs size %d)\n",
604*4882a593Smuzhiyun r, irq, bs->fifo_size);
605*4882a593Smuzhiyun
606*4882a593Smuzhiyun return 0;
607*4882a593Smuzhiyun
608*4882a593Smuzhiyun out_clk_disable:
609*4882a593Smuzhiyun clk_disable_unprepare(clk);
610*4882a593Smuzhiyun out_err:
611*4882a593Smuzhiyun spi_master_put(master);
612*4882a593Smuzhiyun return ret;
613*4882a593Smuzhiyun }
614*4882a593Smuzhiyun
bcm63xx_spi_remove(struct platform_device * pdev)615*4882a593Smuzhiyun static int bcm63xx_spi_remove(struct platform_device *pdev)
616*4882a593Smuzhiyun {
617*4882a593Smuzhiyun struct spi_master *master = platform_get_drvdata(pdev);
618*4882a593Smuzhiyun struct bcm63xx_spi *bs = spi_master_get_devdata(master);
619*4882a593Smuzhiyun
620*4882a593Smuzhiyun /* reset spi block */
621*4882a593Smuzhiyun bcm_spi_writeb(bs, 0, SPI_INT_MASK);
622*4882a593Smuzhiyun
623*4882a593Smuzhiyun /* HW shutdown */
624*4882a593Smuzhiyun clk_disable_unprepare(bs->clk);
625*4882a593Smuzhiyun
626*4882a593Smuzhiyun return 0;
627*4882a593Smuzhiyun }
628*4882a593Smuzhiyun
629*4882a593Smuzhiyun #ifdef CONFIG_PM_SLEEP
bcm63xx_spi_suspend(struct device * dev)630*4882a593Smuzhiyun static int bcm63xx_spi_suspend(struct device *dev)
631*4882a593Smuzhiyun {
632*4882a593Smuzhiyun struct spi_master *master = dev_get_drvdata(dev);
633*4882a593Smuzhiyun struct bcm63xx_spi *bs = spi_master_get_devdata(master);
634*4882a593Smuzhiyun
635*4882a593Smuzhiyun spi_master_suspend(master);
636*4882a593Smuzhiyun
637*4882a593Smuzhiyun clk_disable_unprepare(bs->clk);
638*4882a593Smuzhiyun
639*4882a593Smuzhiyun return 0;
640*4882a593Smuzhiyun }
641*4882a593Smuzhiyun
bcm63xx_spi_resume(struct device * dev)642*4882a593Smuzhiyun static int bcm63xx_spi_resume(struct device *dev)
643*4882a593Smuzhiyun {
644*4882a593Smuzhiyun struct spi_master *master = dev_get_drvdata(dev);
645*4882a593Smuzhiyun struct bcm63xx_spi *bs = spi_master_get_devdata(master);
646*4882a593Smuzhiyun int ret;
647*4882a593Smuzhiyun
648*4882a593Smuzhiyun ret = clk_prepare_enable(bs->clk);
649*4882a593Smuzhiyun if (ret)
650*4882a593Smuzhiyun return ret;
651*4882a593Smuzhiyun
652*4882a593Smuzhiyun spi_master_resume(master);
653*4882a593Smuzhiyun
654*4882a593Smuzhiyun return 0;
655*4882a593Smuzhiyun }
656*4882a593Smuzhiyun #endif
657*4882a593Smuzhiyun
658*4882a593Smuzhiyun static const struct dev_pm_ops bcm63xx_spi_pm_ops = {
659*4882a593Smuzhiyun SET_SYSTEM_SLEEP_PM_OPS(bcm63xx_spi_suspend, bcm63xx_spi_resume)
660*4882a593Smuzhiyun };
661*4882a593Smuzhiyun
662*4882a593Smuzhiyun static struct platform_driver bcm63xx_spi_driver = {
663*4882a593Smuzhiyun .driver = {
664*4882a593Smuzhiyun .name = "bcm63xx-spi",
665*4882a593Smuzhiyun .pm = &bcm63xx_spi_pm_ops,
666*4882a593Smuzhiyun .of_match_table = bcm63xx_spi_of_match,
667*4882a593Smuzhiyun },
668*4882a593Smuzhiyun .id_table = bcm63xx_spi_dev_match,
669*4882a593Smuzhiyun .probe = bcm63xx_spi_probe,
670*4882a593Smuzhiyun .remove = bcm63xx_spi_remove,
671*4882a593Smuzhiyun };
672*4882a593Smuzhiyun
673*4882a593Smuzhiyun module_platform_driver(bcm63xx_spi_driver);
674*4882a593Smuzhiyun
675*4882a593Smuzhiyun MODULE_ALIAS("platform:bcm63xx_spi");
676*4882a593Smuzhiyun MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
677*4882a593Smuzhiyun MODULE_AUTHOR("Tanguy Bouzeloc <tanguy.bouzeloc@efixo.com>");
678*4882a593Smuzhiyun MODULE_DESCRIPTION("Broadcom BCM63xx SPI Controller driver");
679*4882a593Smuzhiyun MODULE_LICENSE("GPL");
680