firmware: qcom: scm: Add support for ARM64 SoCs

Hello Kumar Gala,

The patch 93a30f70d97e: "firmware: qcom: scm: Add support for ARM64 SoCs" from May 12, 2016, leads to the following static checker warning:

	drivers/firmware/qcom_scm-64.c:154 qcom_scm_call()
	warn: unsigned 'desc->res.a0' is never less than zero.

drivers/firmware/qcom_scm-64.c
127 do {
128 mutex_lock(&qcom_scm_lock);
129
130 cmd = ARM_SMCCC_CALL_VAL(ARM_SMCCC_STD_CALL,
131 qcom_smccc_convention,
132 ARM_SMCCC_OWNER_SIP, fn_id);
133
134 do {
135 arm_smccc_smc(cmd, desc->arginfo, desc->args[0],
136 desc->args[1], desc->args[2], x5, 0, 0,
137 &desc->res);
138 } while (desc->res.a0 = QCOM_SCM_INTERRUPTED);
139
140 mutex_unlock(&qcom_scm_lock);
141
142 if (desc->res.a0 = QCOM_SCM_V2_EBUSY) {
143 if (retry_count++ > QCOM_SCM_EBUSY_MAX_RETRY)
144 break;
145 msleep(QCOM_SCM_EBUSY_WAIT_MS);
146 }
147 } while (desc->res.a0 = QCOM_SCM_V2_EBUSY);
148
149 if (args_virt) {
150 dma_unmap_single(dev, args_phys, alloc_len, DMA_TO_DEVICE);
151 kfree(args_virt);
152 }
153
154 if (desc->res.a0 < 0)

                    ^^^^^^^^^^^^^^^^

This is never true. It's an unsigned long now but probably it should be changed to an int?

   155                  return qcom_scm_remap_error(desc->res.a0);
   156  
   157          return 0;
   158  }

regards,
dan carpenter