2 * Copyright © 2013 Keith Packard <keithp@keithp.com>
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; version 2 of the License.
8 * This program is distributed in the hope that it will be useful, but
9 * WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
13 * You should have received a copy of the GNU General Public License along
14 * with this program; if not, write to the Free Software Foundation, Inc.,
15 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
20 static uint8_t ao_spi_mutex[LPC_NUM_SPI];
22 static struct lpc_ssp * const ao_lpc_ssp[LPC_NUM_SPI] = { &lpc_ssp0, &lpc_ssp1 };
24 #define tx_busy(lpc_ssp) (lpc_ssp->sr & ((1 << LPC_SSP_SR_BSY) | (1 << LPC_SSP_SR_TNF))) != (1 << LPC_SSP_SR_TNF)
25 #define rx_busy(lpc_ssp) (lpc_ssp->sr & ((1 << LPC_SSP_SR_BSY) | (1 << LPC_SSP_SR_RNE))) != (1 << LPC_SSP_SR_RNE)
27 #define spi_loop(len, put, get) do { \
29 /* Wait for space in the fifo */ \
30 while (tx_busy(lpc_ssp)) \
36 /* Wait for byte to appear in the fifo */ \
37 while (rx_busy(lpc_ssp)) \
46 ao_spi_send(void *block, uint16_t len, uint8_t id)
49 struct lpc_ssp *lpc_ssp = ao_lpc_ssp[id];
51 spi_loop(len, *b++, (void));
55 ao_spi_send_fixed(uint8_t value, uint16_t len, uint8_t id)
57 struct lpc_ssp *lpc_ssp = ao_lpc_ssp[id];
59 spi_loop(len, value, (void));
63 ao_spi_recv(void *block, uint16_t len, uint8_t id)
66 struct lpc_ssp *lpc_ssp = ao_lpc_ssp[id];
68 spi_loop(len, 0xff, *b++ =);
72 ao_spi_duplex(void *out, void *in, uint16_t len, uint8_t id)
76 struct lpc_ssp *lpc_ssp = ao_lpc_ssp[id];
78 spi_loop(len, *o++, *i++ =);
82 ao_spi_get(uint8_t id, uint32_t speed)
84 struct lpc_ssp *lpc_ssp = ao_lpc_ssp[id];
86 ao_mutex_get(&ao_spi_mutex[id]);
88 /* Set the clock prescale */
89 lpc_ssp->cpsr = speed;
93 ao_spi_put(uint8_t id)
95 ao_mutex_put(&ao_spi_mutex[id]);
99 ao_spi_channel_init(uint8_t id)
101 struct lpc_ssp *lpc_ssp = ao_lpc_ssp[id];
104 lpc_ssp->cr0 = ((LPC_SSP_CR0_DSS_8 << LPC_SSP_CR0_DSS) |
105 (LPC_SSP_CR0_FRF_SPI << LPC_SSP_CR0_FRF) |
106 (0 << LPC_SSP_CR0_CPOL) |
107 (0 << LPC_SSP_CR0_CPHA) |
108 (0 << LPC_SSP_CR0_SCR));
110 /* Enable the device */
111 lpc_ssp->cr1 = ((0 << LPC_SSP_CR1_LBM) |
112 (1 << LPC_SSP_CR1_SSE) |
113 (LPC_SSP_CR1_MS_MASTER << LPC_SSP_CR1_MS) |
114 (0 << LPC_SSP_CR1_SOD));
116 /* Drain the receive fifo */
117 for (d = 0; d < LPC_SSP_FIFOSIZE; d++)
127 lpc_ioconf.pio0_6 = ao_lpc_alternate(LPC_IOCONF_FUNC_PIO0_6_SCK0);
131 lpc_ioconf.pio0_10 = ao_lpc_alternate(LPC_IOCONF_FUNC_PIO0_10_SCK0);
135 lpc_ioconf.pio1_29 = ao_lpc_alternate(LPC_IOCONF_FUNC_PIO1_29_SCK0);
139 #error "No pin specified for SCK0"
141 lpc_ioconf.pio0_8 = ao_lpc_alternate(LPC_IOCONF_FUNC_MISO0);
142 lpc_ioconf.pio0_9 = ao_lpc_alternate(LPC_IOCONF_FUNC_MOSI0);
144 /* Enable the device */
145 lpc_scb.sysahbclkctrl |= (1 << LPC_SCB_SYSAHBCLKCTRL_SSP0);
147 /* Turn on the clock */
148 lpc_scb.ssp0clkdiv = 1;
150 /* Reset the device */
151 lpc_scb.presetctrl &= ~(1 << LPC_SCB_PRESETCTRL_SSP0_RST_N);
152 lpc_scb.presetctrl |= (1 << LPC_SCB_PRESETCTRL_SSP0_RST_N);
153 ao_spi_channel_init(0);
159 lpc_ioconf.pio1_15 = ao_lpc_alternate(LPC_IOCONF_FUNC_PIO1_15_SCK1);
163 lpc_ioconf.pio1_20 = ao_lpc_alternate(LPC_IOCONF_FUNC_PIO1_20_SCK1);
167 #error "No pin specified for SCK1"
171 lpc_ioconf.pio0_22 = ao_lpc_alternate(LPC_IOCONF_FUNC_PIO0_22_MISO1);
175 lpc_ioconf.pio1_21 = ao_lpc_alternate(LPC_IOCONF_FUNC_PIO1_21_MISO1);
179 #error "No pin specified for MISO1"
183 lpc_ioconf.pio0_21 = ao_lpc_alternate(LPC_IOCONF_FUNC_PIO0_21_MOSI1);
187 lpc_ioconf.pio1_22 = ao_lpc_alternate(LPC_IOCONF_FUNC_PIO1_22_MOSI1);
191 #error "No pin specified for MOSI1"
194 /* Enable the device */
195 lpc_scb.sysahbclkctrl |= (1 << LPC_SCB_SYSAHBCLKCTRL_SSP1);
197 /* Turn on the clock */
198 lpc_scb.ssp1clkdiv = 1;
200 /* Reset the device */
201 lpc_scb.presetctrl &= ~(1 << LPC_SCB_PRESETCTRL_SSP1_RST_N);
202 lpc_scb.presetctrl |= (1 << LPC_SCB_PRESETCTRL_SSP1_RST_N);
203 ao_spi_channel_init(1);
204 #endif /* HAS_SPI_1 */